The English language has a special class of verbs called modals: >will, would, can, could, shall, should, may, might, and must. Although modal verbs are useful to express various tenses, moods, and conditions, they can be minefields.

  • Christians must do this.
  • Pastors shall do this.
  • Men or women should do this.

Modals like must, shall, and should imply certainty, obligation, and necessity. They can impede dialogue and close the subject. They sometimes invite antagonism because most of us don’t like being addressed in demanding tones.

But not just discussion and tone are at risk with modal verbs. So is the authority of God.

Traditions of the Elders

The religious leaders of Jesus’s day had a bad habit of using must where may was appropriate. The law of Moses commanded certain things, like observing the Sabbath or celebrating Passover, but the religious leaders added their own rules that were more detailed and concrete than the principles of the Bible. These regulations tended to distract people and, in some cases, even contradict the law.

In their Gospel accounts, both Matthew and Mark tell a story about some religious leaders who asked Jesus, “Why do your disciples break the tradition of the elders? For they do not wash their hands when they eat” (Matt. 15:2; cf. Mk. 7:5). Their concern was not hygiene, but ritual purity. Under the law, the priests were commanded to wash their hands before leading worship as a visible expression of the holiness of God (Ex. 30:17-21).

By the first century, though, it wasn’t just the priests who were required to wash their hands, and it wasn’t just before leading worship. Everyone who wanted to be clean had to wash their hands constantly—after sleeping, before eating, after cutting hair, and more. These extra-biblical rules separated them from the people to whom they were called to be a light (Is. 49:6).

Thus, Jesus replied to the religious leaders, “And why do you break the commandment of God for the sake of your tradition?” (Matt. 15:6). He then applied Isaiah’s prophecy to them: “This people honor me with their lips, but their heart is far from me; in vain do they worship me, teaching as doctrines the commandments of men” (Matt. 15:8-9; c. Mk. 7:6-7).

They weren’t just doing this with ritual washing. “Many such things you do,” Jesus said (Mk. 7:13). They were taking permissible things and making them required. They were using must in places where may was appropriate.

Authority of God

The irony, of course, is that the religious leaders thought they had a high view of the Bible when, in fact, they had a low view of it. They didn’t think the Bible was sufficient. They added descriptive rules because they thought the truths of the Scriptures were too vague.

In their effort to protect the Bible, though, they were actually failing to honor its unique authority and, by extension, failing to worship God. Tim Keller explains,

Jesus is saying, “If you fail to honor the unique authority of the Bible, you fail to worship God. If you let human traditions, what the experts say, what your heart says—if you let anything else have equal authority with the Bible, you fail to worship God. . . . The authority of the Bible and the authority of God stand or fall together. You can’t have one without the other.”

Keller observes, “This is a remarkably, astonishingly high view of the Bible, in which Jesus is seeing the Bible not as a human product, but as something divine.”

Purpose of the Bible

By adding their own rules and regulations, the religious leaders revealed that they thought the purpose of the Bible was to make people feel obedient and righteous. But this isn’t the purpose of the Scriptures.

The purpose of the Bible is to invite people—all kinds of people—into an intimate, loving, covenant relationship with God. Thus, the Scriptures testify about all kinds of people knowing and being known by God—thinkers (Luke) and feelers (David), city planners (Nehemiah) and queens (Esther), Jews (Paul) and Gentiles (Cornelius). Some are full of passion and zeal (Peter). Others are judicious and measured (Deborah). The Lord creates and calls people from all kinds of personalities, histories, families, cultures, languages, and traditions. He delights in multiformity.

In these diverse contexts, God gives his people the freedom to seek him in various ways and to live out the truths of the Bible in different forms. As Paul explained to the Corinthians, “I have become all things to all people, that by all means I might save some. I do it all for the sake of the gospel, that I may share with them in its blessings” (see 1 Cor. 9:19-23). In other words, he kept must in its proper place and let may guide his contextual application.

When to Use Must

Writers can take caution from the interaction between Jesus and the religious leaders. When we feel strongly about something, modal verbs that convey certainty and obligation may subconsciously leap into our writing. Our personal convictions can tempt us to use must or should in ways that go beyond the principles of the Bible.

  • “Whoever would be great among you must be your servant” (Mk. 10:43-44) does not mean that we must avoid pursuing executive positions, speaking truth to power, and negotiating profitable salaries.
  • “You also must be ready, for the Son of Man is coming at an hour you do not expect” (Lk. 12:40) does not mean that we must stockpile canned goods, wear paltry clothing, and forego long-term investments.
  • “Their wives likewise must be dignified, not slanderers, but soberminded, faithful in all things” (1 Tim. 3:11) does not mean that they must have no opinions, only wear skirts, and homecook every meal.

For this reason, after I’ve finished writing an article, I do one last scan for must and should to see whether I’ve used them wisely. In most cases, I replace them with can, could, may, or might. These modals imply permission, possibility, and ability. They acknowledge that the view expressed is my opinion. They recognize that there are other ways to live out a particular truth or command. They invite response and dialogue.

There is, of course, a place for must. But it is rare and intimately tied to Scripture. For where the Lord has not written a must, neither should I.