The reliability of the New Testament documents hinges on their historicity, genuine character, accuracy, transmission, and supernatural claims.


The reliability of the New Testament documents faces several challenges. First, is the Jesus of the Synoptic Gospels (Matthew, Mark, and Luke) a real, historical character, or are these accounts more of a fictional narrative? Second, does the Gospel according to John contradict the Jesus of the Synoptic Gospels? Third, is the early church history as recorded in the Book of Acts historically accurate and coherent? Fourth, are the New Testament Epistles written by the individuals purported to be their authors? Fifth, do other writings exist that should be added to the New Testament canon? Sixth, how can we be sure that the original documents have been faithfully copied and made available to us today? Finally, can we trust the reliability of books that record supernatural events like the resurrection of Jesus?

Many people today harbor the notion that the distinctively Christian Scriptures collected together as the New Testament can hardly be trusted in what they teach. Ironically, there has never been more evidence readily available that actually supports their reliability. Of course, historical research can never confirm or refute theological claims (e.g., Jesus died for humanity’s sins), but without historical facts (e.g., Jesus lived and died) the theology has no foundation.

Historicity of the Synoptic Gospels

The Synoptic Gospels (Matthew, Mark and Luke) contain the primary material scholars use in the “quest of the historical Jesus”. They were probably written within one generation of Jesus’ death in A.D. 30, while eyewitnesses of his ministry were still alive, and by those who were either close companions of Jesus or close associates of those companions. Luke 1:1-4 suggests a careful, historical process of composition, and the overall genre of the Synoptics most closely resembles ancient biographies rather than novels or works of fiction. The oral cultures of the first-century Jewish and Roman world cultivated sophisticated skills of memorization, enabling those who wanted to pass on information accurately by word-of-mouth to do so for long periods of time in ways largely unparalleled in our world today. The differences among the Synoptics match the flexibility with which oral storytellers often recounted that information, along with the theological distinctives and emphases that each writer wanted to highlight. Apparent contradictions among parallel Gospel accounts can usually be explained by the historical conventions of the day. In a world without quotation marks, or any felt need for them, communicating another person’s intent in one’s own words was completely acceptable. Sometimes the gospel writers each excerpt different portions of a larger whole, sometimes they use different degrees of precision, and they regularly arrange their material topically as well as chronologically.

At least a dozen extra-biblical references in non-Christian (Jewish, Greek, and Roman) sources in the earliest centuries of the Christian era (Josephus, Thallus, Suetonius, Tacitus, Pliny, Mara ben Serapion, Lucian, and several Talmudic tractates) confirm the main contours of the Synoptics: Jesus’ birth out of wedlock, his intersection with the ministry of John the Baptist, the existence of his brother James, his gathering of disciples, including five who are named, his running afoul of the Jewish leaders in interpretations of the law, his working “wondrous feats,” and his being deemed “a sorcerer who led Israel astray.” We learn that he was crucified under Pontius Pilate (and thus between A.D. 26-36), that his followers believed he was the Messiah and believed that he had been resurrected, and that his death did not put an end to those beliefs. Instead, his followers rather quickly began meeting together and “singing hymns to him as if he were a god.”

Historicity of John’s Gospel

A sizable majority of John’s Gospel contains different but not contradictory information to what the Synoptics present. Whereas Matthew and Luke most likely knew, used and supplemented Mark, there does not appear to be any literary relationship between John and any of the Synoptics. This fourth Gospel was most likely written a generation later (in the 90s rather than the 60s), by one of the closest followers of Jesus, in his own idiom, influenced by a lifetime of preaching about Jesus, selecting information that had not been previously highlighted in writing. All this was for a community of Christians in and around Ephesus wrestling with the twin challenges of hostile local synagogues, who were increasingly excommunicating members who acknowledged they worshiped Jesus, and the inroads of a syncretistic Greek “Christian” movement known as Gnosticism that denied Jesus’ real physical nature. It is only from John, for example, we learn about Jesus’ roughly three-year ministry, because several of his trips to Jerusalem at festival times are described and can be dated. But John does this not to help us reconstruct a chronology of Jesus’ life but because of his theological conviction that Jesus’ teaching on those occasions showed that he was the fulfillment of the true meaning of the various Jewish festivals. What we learn about the chronology of Jesus’ life emerges incidentally; such details, then, are not likely invented but more likely accurate. Geographical and topographical references are also more abundant in John, and they have been consistently corroborated by archeological finds (e.g., the pools of Bethesda and Siloam, Jacob’s well, Solomon’s portico, Gabbatha, Bethany, etc.). Even John’s very different style and contents of Jesus’ teaching does appear on occasion in the Synoptics (nowhere more dramatically than in Matt. 11:27/Luke 10:22), and conceptual parallels arise on every page of the Fourth Gospel.

Historicity of Acts

The New Testament contains only one book with the genre or contents of the Acts of the Apostles. This is a theologically rich and artistically refined work of history. The number of characters and places in this selective account of key events in the first generation of church history that have been confirmed is staggering. From non-Christian works alone, we know of Annas, Claudius, Gamaliel, Caiaphas, James, Gallio, Agrippa I and II, Sergius Paulus, Felix, Drusilla, Festus, Bernice, and others. Every city and location which has been excavated has been shown to be as Acts describes them, complete with specific synagogues, theaters, stoa, ports, roads, rivers, and more. Particularly significant is how Luke gets right the names of the rulers in the various locations, especially since in some instances they varied quite a bit in a given region or from one time period to the next. These include the Sanhedrin, the Italian Regiment, tetrarchs, proconsuls, magistrates, politarchs, the Areopagus, city clerk and the “chief man” (on the island of Malta). The very fact that one can mesh Acts with the more fragmentary and sometimes incidental allusions to Paul’s life in his letters sets Acts off from historical novels, modern and ancient. That one can generate a plausible, detailed chronology of the events depicted in Acts, again especially in comparison with Paul’s letters, and chart his missionary journeys as coherent and sensible travels, further suggests Acts is historical.

Authorship of New Testament Epistles

A significant question with the New Testament epistles is if they were really penned by the individuals to whom they are attributed. Almost all scholars agree that Romans, 1 and 2 Corinthians, Galatians, Philippians, 1 Thessalonians and Philemon are genuinely Pauline. Some doubt surrounds Colossians and 2 Thessalonians; more doubt, with Ephesians; and the greatest skepticism, with the Pastoral Epistles (1 and 2 Timothy, Titus). But in fact good cases can still be made for Paul having written each of these letters. It is interesting that the complaints about 2 Thessalonians and Ephesians often center on their being too similar to 1 Thessalonians and Colossians, respectively, while the style of the Pastorals is said to be too different from the undisputed Paulines. Paul’s use of scribes (Rom. 16:22) and/or possible co-authors (note the people in addition to Paul mentioned in the first verses of 1 and 2 Corinthians, Colossians, and 1 and 2 Thessalonians) must also be factored in, especially when scribes were sometimes given the freedom to write up in their own styles the thoughts of those employing them.

An interesting dimension of a number of Paul’s letters, penned in the 50s, especially Romans, 1 Corinthians and 1 Thessalonians are the quotations of and allusions to Jesus’ teachings that Paul could not have gotten simply by consulting a Gospel, since none had yet been written. These references thus show that a reliable oral tradition of Jesus’ teachings was circulating. Topics ranged from divorce and remarriage (1Cor. 7:10; cf. Matt. 19:9), to receiving money for ministry (1Cor. 9:14; cf. Luke 10:7), to the “words of institution at the Last Supper” (1Cor. 11:23-25; cf. Luke 22:19-20), to the return of Christ (1Thess. 5:2-4; cf. Matt. 24:42-44) to non-retaliation and enemy love (Rom. 12:17-20; cf. Luke 6:27b-28a), for starters. In other cases, parallels between Paul and Jesus are conceptual rather than verbal, but still close enough to give the lie to the notion that Paul was the true founder of Christianity, substantially distorting the message of Jesus. Examples include Paul’s emphasis on justification by faith (Rom. 3:21-25, Gal. 2:15-21) compared with Jesus’ parable of the Pharisee and tax collector (Luke 18:9-14), love as the fulfillment of the Law (Gal. 5:14, Matt. 22:37-40), and countercultural affirmation of women in various roles typically reserved for men (Luke 10:38-42, Rom. 16:1, 7).

Hebrews through Revelation does not present as many issues, though the question of pseudonymous authorship does recur. Nevertheless, again a good case can be made that James and Jude were indeed written by half-brothers of Jesus, perhaps as early as the late 40s and certainly by the 60s. This letter is filled with allusions to Jesus’ teachings, especially from the Sermon on the Mount/Plain, again most likely before James could have consulted written accounts. Hebrews is anonymous in all of its early manuscripts, and the early church debated whether to attribute it to Paul or to one of his associates. But the apparent allusions to the expulsion of Jews from Rome in 49 (Heb. 10:34) and the fact that none of the Roman Christians had yet been martyred (12:4), no longer the case after 64, suggest it should be dated between these specific years. First and Second Peter are dramatically different in style and contents from each other, suggesting to many that the second of these letters comes from someone other than Peter in a different context at a much later date. But a scribe may be responsible for the polished Greek of 1 Peter, while 2 Peter seems to be deliberately put in a flowery, Asiatic style for the rhetorical emphasis it would generate. Alternately, 2 Peter 1:15 may suggest that this letter was completed posthumously by one of Peter’s disciples. First John is entirely anonymous, while 2 and 3 John are attributed simply to “the elder,” but their styles and contents are very similar. Revelation is attributed to a prophet named John (Rev. 1:1, 4, 9; 22:8), and despite differences, mostly related to contents and genre, is still more similar in style to the other writings the early church attributed to John than to any other documents we know about. That this was John, the son of Zebedee and disciple of Jesus by that name, is still very plausible.

Books Outside the New Testament Canon

Other issues affect the entire New Testament, rather than just one individual book or section. Why distinguish the twenty-seven canonical books from the Gnostic literature or from the so-called New Testament apocrypha? Early Christian discussions suggest that the main criteria included “apostolicity” (books coming from apostles or their close associates, in other words first-century works), “orthodoxy” (books carrying on the story line of the Israelite Scriptures, internally consistent and in keeping with the earliest known apostolic teaching), “catholicity” (widely accepted as authoritative and relevant, not just limited to one location or sect within emerging Christianity), and “inspired” (having the ring of truth and used by the Spirit for distinctively edifying and maturing purposes). The last of these was doubtless the most subjective, but the first three mark the canon off from other competing works reasonably clearly. Much of the Gnostic literature involves Jesus supposedly offering select followers secret, esoteric teachings after his resurrection, often involving the cosmology of the universe with little similarity to the topics discussed in the canonical texts and without the connected narrative form that characterizes the New Testament Gospels. Much of the apocrypha fills in perceived gaps in the canonical accounts of Jesus’ life and the apostles’ ministry, often with clearly legendary information.

Transmission of the New Testament Manuscripts

What about the transmission of the text of the New Testament, especially when scholars point out that there may be as many as 400,000 textual variants in the 25,000 fragmentary, partial or complete copies of these texts in Greek and other ancient languages spanning more than thirteen centuries before the invention of the printing press? Of course this means, on average, only sixteen unique variants per manuscripts, and the vast majority of these involved variations in the spelling of words; the use or non-use of an article, conjunction or particle; or slight variations in syntax. The vast majority also came from the most recent centuries during the period of copying texts by hand. Only about 1500 merit inclusion in the textual footnotes of the United Bible Societies’ Greek New Testament, while typical English translations often include about 300-400 of the most interesting in their footnotes. Readers can see for themselves that very few affect significant issues of meaning. The only two that involve more than one or two verses are Mark 16:9-20 and John 7:53-8:11, and it seems clear that these were not original to the Gospels that now contain them. Most importantly, no doctrine or ethical teaching of Christianity depends solely on one or more disputed texts.

The Question of Miracles

But can we believe in documents as filled with miracles as the New Testament is? If one a priori postulates an anti-supernatural world view, then no, but then one is no longer engaging in historical investigation. The claim that natural explanations are always more probable, even if one does not rule out supernatural explanations up front, is itself a belief that cannot be demonstrated empirically and that unduly denigrates the role of trustworthy testimony as the bedrock of historiography. It also flies in the face of thousands of modern-day experiences of ordinary people all around the globe who have witnessed instantaneous healings (and similar events) after public, concerted Christian prayer. Claims about miracles should neither be written off a priori nor uncritically accepted; they should be tested like any other historical affirmations. What sets the New Testament miracles off from accounts in many other kinds of literature is their consistent link to the arrival or inauguration of God’s reign in the person of Jesus and the movement he began (Matt. 12:28; Luke 11:20). Claims about similarities with other ancient miracle stories break down on careful inspection; the closest parallels are all post-Christian, too late to have influenced the New Testament writers. Partially similar pre-Christian parallels usually cluster around gods or goddesses or heroes from some dim, mythical past and are not attached to recent people known to have lived real human lives. This is especially the case when one examines the resurrection of Jesus, the most spectacular and significant of the foundational Christian miracles.

All in all, the support for the reliability of the New Testament is substantial enough to sustain Christian faith, even if it is not so overwhelming as to compel one to believe.

Further Reading

  • Blomberg, Craig L. The Historical Reliability of the New Testament. Nashville: B & H, 2016.
  • Bauckham, Richard. Jesus and the Eyewitnesses: The Gospels as Eyewitness Testimony, 2nd Grand Rapids: Eerdmans, 2017.
  • Keener, Craig S. Acts: An Exegetical Commentary, 4 vols. Grand Rapids: Baker, 2012-15.
  • Keener, Craig S. Miracles: The Credibility of the New Testament Accounts, 2 vols. Grand Rapids: Baker, 2012.
  • Kruger, Michael J. Canon Revisited: Establishing the Origins and Authority of the New Testament Books. Wheaton: Crossway, 2012.
  • Köstenberger, Andreas J., L. Scott Kellum and Charles L. Quarles. The Cradle, The Cross, and the Crown: An Introduction to the New Testament, 2nd ed. Nashville: B&H, 2016.

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