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Definition

God has given the power of the sword to governments and the power of the keys to churches, and he intends for them to work separately but cooperatively toward the greater end of worship.

Summary

Governments should employ the sword in order to protect life, enable the cultural mandate, and provide a platform for the work of the church. They are guardians of this present age. Churches should exercise the keys of the kingdom in order to testify to King Jesus, his message, and his people. They are witnesses of the age to come.

To summarize the relationship between church and state in a sentence, we could say, God has given the power of the sword to governments and the power of the keys to churches, and he intends for them to work separately but cooperatively toward the greater end of worship.1 Both fail often and miserably in their jobs. Yet we need to first understand the blueprint in order to better identify departures from it. Let’s therefore unpack that summary sentence one phrase at a time.

God…

As the creator of all things, God is the ruler of all things. The Author, by definition, possesses author-ity. God’s rule is comprehensive, covering all things. It is legitimate, being morally right. It is absolute, never subject a higher authority.

The nations may rage against him now. American judges and Chinese presidents might deny his existence. Yet God’s future judgment over both ruled and ruler alike demonstrates his rule in the present. Judgment tomorrow means rule today. He will judge every judge and president by his standards, not theirs. Therefore, the Psalmist declares, “Say among the nations, ‘The Lord reigns!’” and “he will judge the peoples with equity” (96:10). Elsewhere, the Psalmist warns: “Now therefore, O kings, be wise; be warned, O rulers of the earth” (2:10). The warning addresses not just the kings and rulers of the biblical world, but the presidents and prime ministers, voters and opinion-makers of today.

In other words, God is not the king of two kingdoms, as some writers put it. Two kingdoms implies two kings. God is the one king of all the nations. Says Jeremiah,

There is none like you, O Lord;
you are great, and your name is great in might.
Who would not fear you, O King of the nations?
For this is your due; for among all the wise ones of the nations
and in all their kingdoms there is none like you. (Jer. 10:6-7)

The story of the Bible is the story of God making his rule, which has been hidden since expelling Adam and Eve from Eden, visible at different times in different ways. Sometimes he made his rule visible through mighty acts of salvation or judgment; sometimes through covenantal signs, such as circumcision and Sabbath keeping and baptism. Most clearly, his rule became visible in the person and work of his Son, who possesses all authority in heaven and earth. The coming of Jesus’ kingdom does not mean God now rules in places where he did not rule before. It means that God’s rule becomes visible and acknowledged in places where it was not before.

All the earth, in other words, divides between those places where Christ’s rule is accepted and places where it is resisted (see Psa. 2:1-3). There are no “neutral” spaces, not in the public square, not elsewhere, as popular as the idea of religious “neutrality” may be in the democratic West. The public square, in fact, is nothing more than a battleground of gods, which everyone enters on behalf of their God or gods, whether the god’s name is Jesus or Allah, sex or the stock market.

Therefore, the Psalmist, again addressing the nations and their kings, warns, “Kiss the Son, lest he be angry, and you perish in the way” (Psa. 2:12).

…Has Given the Power of the Sword to Government…

If Jesus is king over all the earth—over every square inch, as Abraham Kuyper famously put it—does that mean Christians should use the power of government to bring all things into subjection to him? Should they criminalize all sin and force people to worship him with the power of the government, like Charlemagne did in the ninth century for Christianity and some Muslims do today for Islam?

Not at all. Jesus rules over every square inch, but he does not rule over every inch in the same way. He grants different authorities to different parties. To parents he gives the power of the rod. To governments he gives the power of the sword. To churches he gives the power of the keys. Yet to none of the parties does God give the authority to coerce true worship or criminalize false worship. Nor does he give governments the authority to criminalize all sin.

Let’s back up. Paul is the one who called the government’s power the power of the sword (Rom. 13:4). Yet the original authorization occurred right after the Flood. God had just repeated the charge he had given to Adam: “Be fruitful and multiply and fill the earth” (Gen. 9:1,7). Yet now in this post-Fall world, to keep the Cains from killing the Abels, God included this proviso:

And for your lifeblood I will require a reckoning: from every beast I will require it and from man. From his fellow man I will require a reckoning for the life of man.

“Whoever sheds the blood of man,

by man shall his blood be shed,

for God made man in his own image.

God did not establish a particular form of government in these verses, whether monarchy, aristocracy, or democracy. Rather, he handed human beings the basic ingredient necessary for gathering together and forming governments in this fallen world: the ability to use morally legitimate coercive force for his purposes in justice.

Several further things are worth noticing in this passage. First, the government’s authority comes from God. The U. S. Declaration of Independence might say that governments “derive their just powers from the consent of the governed,” as if to say any powers not derived from the people’s consent is unjust. But that’s not what God said to Noah. Three times he said he would “require” these things. Their just powers derive from him. A person might withdraw his or her consent, but that doesn’t make a government’s authority necessarily unjust or immoral. Paul would later say, “For there is no authority except from God, and those that exist have been instituted by God. Therefore, whoever resists the authorities resists what God has appointed” (Rom. 13:2). Paul does not mean God approves of everything any given government does, or that we should obey governments no matter what. He does mean their authority comes from him, and that we should obey them, at least when they act within the jurisdiction he gave.

Second, God does not authorize governments to do whatever they wish. He does not authorize them to redefine marriage or the family. He does not authorize them to tell churches what they must believe or who their members are. He does not authorize them to use force unjustly or indiscriminately, lest the force of these verses boomerang back and indict the government itself. No government is “above” the demands of these verses. Finally, he does not authorize governments to prosecute crimes against him (such as blasphemy or false worship) or to criminalize every sin imaginable (such as adultery or homosexuality). Indeed, it would seem governments must tolerate false religions, so long as they cause no direct harm to human beings: “whoever sheds the blood of man” not “of God.” Besides, how do you recompense God?

Rather, third, God authorizes governments to protect the life of God-imagers. To put it another way, he grants them the ability to establish a basic form of justice we can call “Noahic justice.” Noahic justice is not a maximalist, perfectionist form of justice, of the kind God required of old covenant Israel or the new covenant church: “Be perfect as your heavenly Father is perfect” (Matt. 5:45). Rather, it’s a narrowly defined preservative or protectionist form of justice. God intends all governments in all nations to establish this form of justice on their citizens, whether they acknowledge God or not. “By justice a king builds up the land” (Prov. 29:4). Such justice ensures peace and order (1Tim. 2:2).

Everything a government does—every law it makes, every courtroom ruling it declares, every executive agency code it enforces—it should do for the purpose of protecting and affirming its citizens as God-imagers. Its work of establishing or upholding justice must always be measured by the standard of the imago Dei. Anything that harms, hurts, oppresses, exploits, hinders, tramples upon, degrades, or threatens human beings as God-imagers arguably becomes a target of the government’s opposition. And, by implication, anything that aids, abets, promotes, or encourages a set of conditions that contributes to the ability of God-imagers to live out their vocation of imaging God should be considered as a candidate for possible governmental encouragement. Punish the bad, reward the good, as Paul put it in Romans 13.

Christians will disagree, no doubt, over how far the demands of justice warrant such activity. Does protecting and affirming the imago Dei warrant universal health care, or a progressive tax structure, or a ceiling on carbon dioxide emissions, or national math standards for eighth-graders, or the existence of a federal aviation authority and requirements on commercial airline construction? Different Christians will judge differently. Such debates are good to engage and belong to the category of Christian freedom and prudence. The point here is, we have a basic standard by which to assess our answers and gauge our arguments: what protects and establishes the platform on which God-imagers can fulfill their divine calling as divine imagers?

Martin Luther King Jr. captured the basic idea when he said, “Any law the uplifts human personality is just. Any law that degrades human personality is unjust.”

…And the Power of the Keys to Churches…

If God has given the power of the sword to the state, he has given the power of the keys to churches.

The Bible first talks about the keys in Matthew 16. Jesus first gave the keys to Peter and by extension all the apostles immediately after Peter confesses Jesus as the Christ, the Messiah. Jesus promises to build his church and then says, “I will give you the keys of the kingdom of heaven, and whatever you bind on earth shall be bound in heaven, and whatever you loose on earth shall be loosed in heaven” (v. 19).

Two chapters later, Jesus gives the keys to local churches. Addressing the scenario of a Christian wandering into sin—like a sheep going astray—Jesus encourages the disciples to address a person privately, but eventually before the whole church. If the sinning member refuses to listen to the church, then they should collectively remove him or her from the church. In case someone wonders by what authority a church might remove one of its members, Jesus repeats the line about the keys: “Truly, I say to you, whatever you bind on earth shall be bound in heaven, and whatever you loose on earth shall be loosed in heaven” (Matt. 18:18). While the “you” in chapter 16 is singular, here it is plural, as in “Whatever ya’ll bind on earth….”

What does it mean for a church to exercise the keys by binding and loosing on earth what is bound and loosed in heaven? The short answer is that churches exercise the keys by rendering judgments on the what and the who of the gospel, confessions and confessors. Practically, they do this in preaching and in administrating the ordinances. Through preaching a church says, “This is a right gospel confession.” Through the ordinances, it declares, “This is a true gospel confessor.” To put it programmatically, the keys allow churches to write statements of faith and receive and remove members.

The work of wielding the keys is a judicial activity, like the work of a judge in a courtroom. A judge does not make the law. He interprets it. Then, based on that interpretation, a judge does not make a person actually innocent or guilty, but when he pounds the gavel and declares “guilty” or “not guilty,” the whole legal system will swing in action and treat the person as such. A judge on the bench and a law professor in the classroom might use the exact same words when interpreting a law or offering their judgment of a case. But a judge’s judgments bind. The words “Guilty” or “I pronounce you man and wife” are effectual, because they are backed up by the authority of a government. They enact something.

Similarly, by virtue of the keys of the kingdom, churches don’t “make” the gospel, nor do they “make” people Christians. But they possess an authority the individual Christian does not possess: the ability to represent the kingdom of Christ in formally recognizing people as members of the church, or in removing them. They formally represent Christ in heaven.

…And He Intends for Them to Work Separately…

Now, placing the institutions of church and state side by side, what can we say about their relationship? To begin with, the two institutions should remain “separate,” in the sense that neither should wield the authority God has given to the other. Pastors should not wield the sword. Presidents should not wield the keys. And generally, those separate authorities come with separate jurisdictions or fields of activity. Churches generally should not delve in the intricacies of trade policy, while Congress should not offer counsel on which Bible translations are best or who to receive as members. Nobody wants the Barack Obamas or Donald Trumps deciding on baptisms.

For these reasons, Emperor Constantine should not have involved himself in the Council of Nicaea’s deliberations on the doctrine of the Trinity, at least not in his capacity as emperor. The work of adjudicating doctrine belongs to the holder of the keys, not government. Likewise, the government has no business telling non-governmental organizations, especially churches, that they must be willing to hire gays or lesbians, as a recent candidate for U. S. president argued. The work of choosing the teachers of doctrine (pastors) also belong to the holder of the keys, not government.

Yet on the flip side, we can think of times when churches have encroached upon the work of governments. For instance, John Calvin should not have participated in the prosecution of Michael Servetus for heresy. Christian Scientists should not be allowed to deny medical care to their children by mounting a “religious freedom” defense. The government’s God-given job is to protect the lives of their citizens—“whoever sheds the blood of man”—and barring them from doing so is to usurp the sword. And evangelical preachers should be slow to address issues of public policy unless those issues are explicit in Scripture or clear “by good and necessary consequence,” to borrow language from the Westminster Confession.

In short, nowhere does the Bible envision the wedding of church and state which characterized the Western world from the fourth century to the American Revolution in what’s called “Christendom” or the “Constantinian settlement.” Under this settlement, the emperor and pope or the king and archbishop together ruled a so-called “Christian” empire or nation.2 The biblical arguments for Christendom relied too much on the Mosaic or Davidic or New Covenants, which God had given expressly to his special people. These Christian governors should have looked instead to the Noahic Covenant, which God gave to humanity in common. It offers a much more limited jurisdiction. One might therefore say that everyone from Constantine to Charlemagne to the magistrates of Calvin’s Geneva to Henry the VIII picked up the wrong biblical charter for their sword-wielding work.

That said, the jurisdictions of church and state do overlap. When Emperor Theodosius massacred 7000 Thessalonians in response to the assassination of a military officer, the bishop Ambrose may well have been entirely within his rights to excommunicate “church member” Theodosius for the excessive and unjust manner in which “Emperor” Theodosius was doing his job of wielding the sword. Likewise, we might applaud those Roman Catholic bishops who refused to give the Lord’s Supper to senators Edward Kennedy and Joe Biden for their active support of abortion.

By the same token, a government would be entirely within its right to prosecute a pastor or church who is breaking the law and harming people, as with a church which refused to pay property taxes on its property or which failed to report cases of child abuse.

The challenge today is, most people, including most Christians, misconstrue the separation of church and state. They treat it as being about the origin of ideas, as if to say, when an idea originates in someone’s religion, we should not bring it into the public square and impose it on others. So the non-Christian says to the Christian, “That idea originates in your religion. You can’t impose it on me.” The Christian then goes along with the non-Christian’s argument, because she has grown up in an individualistic culture and fails to recognize the distinction between an individual Christian and the key-wielding institutional church. After all, the separation of church and state applies not to individual Christians, as such, but to churches in their authority-exercising capacity. Furthermore, both the non-Christian and the Christian in this scenario overlook the fact that every idea and every claim of justice originates in someone’s religion, someone’s worship. They overlook the fact that, when the non-Christian talks about the separation of church and state, he means the separation of the state from everyone else’s church, not his own church. He doesn’t think he has a church, and he’s only too happy to impose all of his idolatry on the state. Fortunately for him, no one ever talks about the separation of idolatry and the state.

Ironically, it’s the Bible-reading Christian who possesses faith-based reasons not to impose the whole of her religion in the pluralistic public square. Yes, Christians will argue for what we believe God himself has imposed on all people when he established the jurisdiction of governments, as with criminalizing murder or theft. But no, but we have neither the authority nor ability to criminalize everything the Bible calls sin or to create true worshippers of Jesus by the sword. Our faith is publicly self-limiting. It’s the gods of secularism who have no self-imposed limits. There is nothing in their religion that would prevent them from imposing the whole of their faith on a nation’s citizens. And they do, through legislation, education, and the marketplace.

In short, the separation of church and state is not about the origination of opinions. It doesn’t mean we never “impose” our religion on others since every law establishes someone’s religion, even a law against murder. (Gratefully, most of our gods agree on that particular law.) Rather, a biblically conceived doctrine of the separation of church and state is about jurisdictional authority. It recognizes that God has given one kind of authority to governments (the sword) and another kind to churches (the keys), and neither should usurp the other.

The U. S. Constitution’s First Amendment’s careful phrasing strikes a remarkably good balance. In addition to ensuring the “free exercise” of religion, it says “Congress shall make no law respecting an establishment of religion.” It does not carelessly say “Congress shall not establish religion,” since, again, every law effectively does. This reference to “an establishment” of religion obliquely but helpfully acknowledges the aforementioned distinction between a Christian and an establishment of Christians, a church. Congress doesn’t get to wield the keys. It doesn’t get to organize the adherents of any particular religion, telling them who they are or what they must believe.

…But Cooperatively…

When we think about the separation of church from a biblical perspective, we discover something interesting: it rests upon an underlying foundation of cooperation, at least as God intends it. He means for them to do different things, and even to check one another when necessary, but all that presumes that both are working toward his ends. Both must work to enact his righteousness, each for their part. Governments should do so within the narrow lane of protection. Churches should so with a broader lane of perfection. Yet neither has permission from God to render their respective judgments according to some other god’s version of right and wrong.

Consider again the Last Day and the question that the Lord Jesus will pose to each: “Did you act according to my righteousness?”  The apostle John offers a glimpse of what that day will be like for all who adopted their own standards of righteousness and not God’s:

Then the kings of the earth and the great ones and the generals and the rich and the powerful, and everyone, slave and free, hid themselves in the caves and among the rocks of the mountains, calling to the mountains and rocks, “Fall on us and hide us from the face of him who is seated on the throne, and from the wrath of the Lamb, for the great day of their wrath has come, and who can stand?” (Rev. 6:15-17).

God will hold every ruler and leader, and everyone in every place of the political hierarchy, from slave to free, accountable to the standards of his righteousness.

Too often, however, Christians interpret Jesus’ words about rendering to Caesar what is Caesar and to God what is God’s as if Caesar was somehow outside of God’s jurisdiction. They envision two separate circles—one for Caesar’s things and one for God’s things.

Yet the context of these verses is worth noticing. Jesus asked whose image was on the coin. The people replied, “Caesar’s.” Yet every member of Jesus’ largely Jewish audience would have known that Caesar himself was created in God’s image. Really, what Jesus offered was a big circle with a smaller circle inside of it:

This is why Jesus would later tell Pilate he would have not authority if God had not given it (John 19:11). God intended Caesar—and every government in the history of the world—to do his job in obedience, not rebellion. And there is no third way. Ideally, church and state will cooperate, then, not continually work against one another.

A right understanding of the God-intended cooperation between churches and the government requires a slightly sharper definition of their God-intended jurisdictions. Martin Luther, and John Locke following him, divided the inner and outer person, and then assigned the inner person to the church and the outer person to the government. The trouble with this way of dividing things is, churches must wield the keys of the kingdom based on both inner beliefs and outward actions, as when it excommunicates the man who abandons his wife while professing Christian belief. Governments, too, must account for both the so-called inside and the outside of a person, as when they justly distinguish between manslaughter and pre-meditated murder.

John Calvin and those following him tried to draw a line between the so-called “political” and “spiritual” realms. The trouble with this is, our politics always depend upon religious commitments, and our religious commitments are never politically indifferent but yield political demands.

How then do we describe the Bible’s division of labor? Better than dividing up the work of church and government between two kingdoms, I believe, is dividing them between two ages.  The institutions of government and family belong to the present age of creation. They serve everyone who has been born. The church and its officers belong to the age of new creation, which began at Pentecost and embraces all who have been born again.

The New Testament does mention in passing the distinction between the inner and outer person (2Cor. 4:16). Yet it leans more heavily on the distinction between the “old man” and the “new man”—or life in the flesh versus life in the Spirit. It doesn’t contrast secular and sacred, but between temporal and eternal. One age and its rulers are passing; the other is not. The old man of this present age remains subject to the powers of the world, the flesh, and the devil (Eph. 2:1–3), while the new man of the new age is empowered by the Spirit. The institutions of the present age must rely on coercive authority, whether rod or sword. The institutions of the age to come rely on the indwelling work of the Spirit, the word of God, and the declaration-pronouncing keys.

What’s important to recognize is that the age of creation and new creation presently overlap. They operate simultaneously. The whole person (inner and outer, spiritual and political) lives within the legitimate but fallen institutional structures of creation (family, state). And the whole born again person (inner and outer, spiritual and political) lives by the power of the Spirit within the institutional structures of the new creation (church, ordained elders). Indeed, it’s because these two ages move simultaneously in the present that we can expect Christians in churches to exercise the keys in ways that are both righteous and sinful, and we can expect Christians in government to exercise the sword in ways that are both righteous and sinful. We are “simultaneously justified and sinful,” as Luther put it. Christians need the church and state both.

In short, governments serve to protect this present age of creation, while churches serve to present and proclaim the age of new creation. And God intends for the institutions of both ages to serve one another, at least until he returns, concludes this present age, and ushers in the fullness of the age to come. At that time, the institutions of this present age will pass away or at least transformed beyond imagination (see Matt. 17:24–27; Matt. 22:30). For now, however, the state exists to provide a platform for the church’s work of redemption, while the righteousness and justice of the church serves as a prophetic witness for the state. Insofar as Christians act righteously in either place, they offer non-Christians a model for how they, too, should act in life and in government.

When both church and state behave in justice and righteousness, they can affirm and reinforce one another in places of overlap. They can cooperate.

…Toward the Greater End of Worship

Ultimately, both governments and churches serve God’s purpose of calling all people to worship him, the former indirectly, the latter directly. The government’s work is a prerequisite to the mission of the church and salvation, just as learning to read is a prerequisite to reading the Bible. Common-grace platforms are meant to serve special-grace purposes.

Indeed, this is what we see in Scripture. First, God grants a charter for governments. Then he calls Abraham out of Ur. Genesis 9 comes before Genesis 12 for a reason. Just like God promises to lay down his bow of war and not destroy the earth by a flood, so he means for governments to provide the peace and safety necessary for the storyline of redemption to get under way.

Paul reaffirms this point. In Acts 17, he tells us that God established the boundaries of the nations so “that they should seek God, and perhaps feel their way toward him and find him” (v. 27,). In 1 Timothy 2, he tells us to pray for kings and authorities so that we may live peaceful lives pleasing to God, “who wants all people to be saved and to come to a knowledge of the truth” (v. 4).

Governments finally exist, then, to serve the purposes of worship. People need to be able to walk to church without getting mauled by marauders. They cannot get saved if they are dead. The work of government provides the platform. Protecting religious freedom doesn’t just serve Christians, it serves everyone.

To be sure, looking at the actual biblical record of governments gives Christians reasons to be both discouraged and encouraged along these lines. Some governments in the Bible sheltered God’s people: Abimelech, Pharoah in the time of Joseph, the late Nebuchadnezzar, Cyrus, and the Roman proconsul Festus. Yet many governments sought to devour God’s people: Pharaoh in the time of Moses, Sennacherrub, Pilate, and the Beast of Revelation. Romans 13 calls governments servants; Psalm 2 calls them imposters. Most governments contain both. But some are better than others.

Therefore, Christians should not put too much hope in government, but they shouldn’t give up on it either. Churches need good governments. They enable churches can do their work in peace.

A culture and its political institutions might turn against Christianity, but Christians should strive to make an impact as long as they have opportunity. It can get worse. Just ask the Christians in China or Iran.

Who Should We Vote For?

Perhaps we can summarize this entire essay by answer the question: so who should Christians vote for in the next election?

Christians should vote for the candidate, the party, the legislation, or the ballot measures with a limited but clear view of what the government has been authorized and ordered by God to do: to exercise judgment and establish justice; to build platforms of peace, order, and flourishing; to make sure people are free and not hindered from knowing God and being redeemed.

We don’t want a government who thinks it can offer redemption but a government who views its work as a prerequisite for redemption for all of its citizens. It builds the streets so that you can drive to church; protects the womb so that you can live and hear the gospel; insists on fair-lending and housing practices so that you can own a home and offer hospitality to non-Christians; works for education so that can read and teach your children the Bible; treats all people and races equally so that Christians can join the same churches and present a picture of heaven’s diversity; protects marriage and the family so that husbands and wives can model Christ’s love for the church; polices the streets so that you are free to assemble as churches unmolested and to make an honest living so that you can give money to the work of God.

You might disagree on government involvement in any of these examples. But it’s the grid I want you to see and adopt: government renders judgment to establish peace, order, and prosperity so that the church might do what God calls it to do.

Footnotes

1Throughout this article, I will generally use the term “government” instead of “state.” The latter term fits with the particular kinds of governments people associate with the nation-states of the mid-nineteenth century to the present. The term “government,” however, better applies to a broad range of ruling institutions from throughout history—from the ancient empire to the chief and elders of a migratory indigenous tribe and everything in between.
2It’s worth noting the crucial role that infant baptism plays in constituting this wedding between church and state. Paedobaptism allows citizenship and church membership to largely overlap. Every newborn citizen can be quickly baptized into the church, such that people can speak of Anglican England or Roman Catholic Spain, in a way that arguments for a “Christian America” can never quite get off the ground since the U. S. federal government never established a particular church and because of the comparatively high percentage of Baptist churches. In other words, the practice of infant baptism does not necessitate a wedding between church and state, but it’s conducive to such a wedding in a way that believer’s baptism is not.

Further Reading

  • Martin Luther and John Calvin, On Secular Authority, Harro Höpfl, Cambridge Texts in the History of Political Thought (New York: Cambridge University, 1991).
  • John Locke, A Letter Concerning Toleration, any edition
  • Oliver O’Donovanand Joan Lockwood O’Donovan, editors, From Irenaeus to Grotius: A Sourcebook in Christian Political Thought (Grand Rapids, MI: Eerdmans, 1999).
  • David VanDrunen, Politics After Christendom (Grand Rapids, MI: Zondervan, 2020).
  • Jonathan Leeman, Political Church: The Local Assembly as Embassy of Christ’s Rule (Downers Grove, IL: IVP Academic, 2016).
  • Jonathan Leeman, How the Nations Rage: Rethinking Faith and Politcs in a Divide Age (Nashville, TN: Nelson Books, 2018).
  • Jonathan Leeman, “How the State Serves Salvation,” Ligonier
  • Jonathan Leeman, “Not Two Kingdoms, But Two Ages,” The Gospel Coalition
  • Jonathan Leeman, What Would An Ideal Polity Look Like From a Christian Perspective?, ERLC

This essay is part of the Concise Theology series. All views expressed in this essay are those of the author. This essay is freely available under Creative Commons License with Attribution-ShareAlike (CC BY-SA 3.0 US), allowing users to share it in other mediums/formats and adapt/translate the content as long as an attribution link, indication of changes, and the same Creative Commons License applies to that material. If you are interested in translating our content or are interested in joining our community of translators, please reach out to us.