ABSTRACT: While distinct and written to address different original audiences and situations, the letters of the New Testament express a united and consistent message about God and the gospel of Jesus Christ. Just as the theological continuity and pairing of various letters is explicit, so too the authors who penned the letters knew one another and openly acknowledged the validity and usefulness of each other’s writings. These letters were meant to be read as a whole. By reading each one in light of the others, new riches and depths of understanding may be discovered.

The apostles did not leave a legacy of essays and treatises that explain the teaching of Jesus; they left behind a corpus of letters. These letters were written by a variety of people and differ from one another in their setting, first audience, and occasion. Though there is much we do not know about how and why each of the individual letters was written, the New Testament is not silent on this matter. By looking at the historical information the letters themselves give, we can gain some valuable insights.

This essay will focus on one insight: the historical background to the unity of the apostolic teaching found in these letters. We will see how the authors related to one another, how they affirmed a universal message they taught everywhere, and why we are justified in reading the letters not just as individual writings but also as a complete unity. While many already read the letters in light of one another for canonical and theological reasons (which are valid), the historical case for reading the letters together is not always clearly stated. This essay aims to offer insight on what the New Testament itself says about how the letters came into being and why they hang together.

Let me offer one disclaimer at the outset: we will ignore the letter to the Hebrews almost completely. It is clear from Hebrews 13 that the author was familiar to the first readers, and the manuscript tradition normally incorporates Hebrews in the Pauline letters. Yet the long discussions surrounding its authorship need not distract us here.

Who Wrote the Letters?

Every letter has a writer, and it is important for recipients to know whom the letter is from. Most of the letters start off by mentioning the author’s identity. The apostle Paul always names himself at the start of his letters, the whole section from Romans to Philemon. Sometimes he mentions a coworker: Sosthenes in 1 Corinthians; Timothy in 2 Corinthians, Philippians, and Colossians; and Timothy and Silvanus in 1 and 2 Thessalonians. In each of these letters, however, the authorial voice reverts back to an individual “I,” and this singular voice is always that of Paul.

The apostle Peter also names himself in the two letters that carry his name (1 Peter 1:1; 2 Peter 1:1). Of course, Peter’s name was Simon before Jesus called him (Mark 3:16), and the Aramaic version of Peter is Cephas (John 1:42), the only designation Paul uses for Peter in 1 Corinthians (in Galatians, Paul uses both Peter and Cephas). To add to these three names, Peter introduces himself as Simeon Peter in 2 Peter, the exact form James uses in Acts 15:14.

The third apostle to write letters is John, though he never names himself in either the Gospel or any of the three letters that bear his name. Only in Revelation do we find his name (assuming it is the same author), and there not just once at the beginning of the book, but three times in the opening of the book and once towards its closing (Revelation 1:1, 4, 9; 22:8). In Revelation, it is not his own testimony he declares (John 1:14; 1 John 1:1–3); he serves as a mere servant passing on the direct words that he is told to write.

Brothers of the Lord

This leaves us with two final authors: James and Jude. There are two apostles called James: James the son of Zebedee and brother of John, and James the son of Alphaeus (Mark 3:16–18). The first of these was killed by Herod Antipas in Acts 12:2. From then on, another James continues to play a prominent role in Acts. This James is never disambiguated by the addition of an expression such as “son of X.” So, who is he? Galatians 1:19 teaches us explicitly that James the brother of the Lord was a prominent leader in the early church. Subsequently, this James did not need further introduction.

Therefore, it is reasonable to accept that the letter of James was written by the James who needed no more introduction than simply “James” — namely, the brother of Jesus. (Technically, James is of course a half-brother of Jesus, but since Scripture uses the term brother of Jesus for James, there is no need for us to be more precise.)

This also helps us identify the author of Jude. The names Jude and Judas, though distinguished in English translations, are identical in the underlying Greek. So, who is this Jude/Judas? In Jude 1, he calls himself “a servant of Jesus Christ and brother of James.” This latter designation helps us identify the author. If it is sufficient to simply say that one is a brother of James, it must be the same James who needs no further introduction. Therefore, Jude modestly introduces himself as brother of James, though he could have mentioned that he is a brother of Jesus!

Of the five known authors of the New Testament letters, two turn out to be brothers of Jesus (named in Matthew 13:55), demonstrating how markedly different their attitude had become after the resurrection. Apart from James’s prominent role in Acts and in Galatians 1:19 (and also 2:9), the brothers of Jesus show up as a group somewhat unexpectedly in 1 Corinthians 9:3–5.

This is my defense to those who would examine me. Do we not have the right to eat and drink? Do we not have the right to take along a believing wife, as do the other apostles and the brothers of the Lord and Cephas?

That Paul can mention “the brothers of the Lord” without the need to introduce them any further shows that they were well-known throughout the churches. This wide recognition of the brothers as followers of Jesus adds something to the stories in the Gospels that speak of their earlier rejection of him. Their initial unbelief (John 7:5) had been completely overturned, and the readers must have known this.

One meeting between Jesus and James is in fact mentioned in 1 Corinthians 15:7, where Paul mentions that the risen Lord “appeared to James.” Why this meeting of Jesus and his brother? We can only speculate what took place and what was said. It may have had something to do with James being next in line as an heir of the promises to Abraham and David, which rested on Jesus who had died but then rose from the dead (but Scripture does not disclose anything about this).

Together in Common Cause

Three of these five authors refer to at least one of the others. Paul mentions having met James, Peter, and John on more than one occasion. He expects his audience to know about the brothers of the Lord. Peter talks about Paul’s letters and also mentions the teaching of the apostles (2 Peter 3:2), as does Jude (Jude 17). Since 1 John and the Gospel of John are so tightly related, the references in John’s Gospel to the other apostles may count as well. Only James does not mention other apostles.

Two of the authors are brothers; Peter and John had been partners even before they were called by Jesus; Paul was a regular visitor to Jerusalem. Therefore, the New Testament letters were written by people who knew one another and who, despite their diverse writings, shared a common cause.

Witness of 1 Corinthians

Of all Paul’s letters, 1 Corinthians may be the most specific, addressing situations and questions found in the church of Corinth. The letter also gives us a fascinating glimpse into the historical situations surrounding the writing of letters. For example, when we compare the movements of Paul, Apollos, Prisca and Aquila, and Timothy, it becomes clear that 1 Corinthians was written at the time described in Acts 19:22. Paul wants to return through Macedonia and Achaia and sends Timothy (1 Corinthians 4:17; 16:10) and Erastus to prepare. But rather than waiting to address the various issues in person, Paul decides to write a letter with his apostolic teaching.

Purpose and Provenance of 1 Corinthians

So, why did Paul not wait? First of all, he had received disturbing news about the church. People from the household of Chloe had told Paul about the divisions in the church (1 Corinthians 1:11). Paul uses the first four chapters to address these divisions. In 1 Corinthians 5:1, Paul addresses another problem he had heard about, but here he does not mention who brought the report. It may well be that Paul had learned about the divisions around the Lord’s Supper from Chloe’s people as well (1 Corinthians 11:18), but the text is silent about his exact source.

Second, not only had Paul received a report about the church, but he had also received a letter from the church (1 Corinthians 7:1). In this letter, the Corinthians asked Paul about his teaching on marriage and divorce, and possibly about other issues that Paul introduces with the phrase “now concerning X . . .” (see 1 Corinthians 7:25; 8:1). Paul repeats the phrase again in 1 Corinthians 12:1, but the ensuing discussion of the spiritual gifts may not have been one of the issues asked about in the letter. The close of the previous chapter suggests that at that point Paul had finished writing on the subjects he thought most necessary. “About the other things I will give directions when I come” (1 Corinthians 11:34).

The letter from Corinth to Paul must have been delivered by someone, and at the time of writing the letter three members of the Corinthian church were with Paul (1 Corinthians 16:17). This suggests that Stephanas, Fortunatus, and Achaicus were the ones who had made the trip from Corinth to Ephesus to deliver the letter and possibly even return with the answer.

Putting this all together indicates that the early church was in close contact with one another. Letters were sent; people brought reports on how the churches were doing; Christians visited one another. Churches did not live in isolation; rather, there were contacts and people traveled.

Paul’s Universal Teaching

Despite the specificity of 1 Corinthians in dealing with contextually determined problems, Paul goes to great lengths to emphasize that he is not telling the Corinthians something he does not teach elsewhere. That is, Paul wants the Corinthians to know that his instructions are the universal teaching.

He starts emphasizing this point in the opening of the letter by including the phrase “together with all those who in every place call upon the name of our Lord Jesus Christ, both their Lord and ours” (1 Corinthians 1:2). The Corinthian church is connected with the believers everywhere. Paul also presents the sending of Timothy in this light; Timothy is to remind the Corinthians of Paul’s ways in Christ, “as I teach them everywhere in every church” (1 Corinthians 4:17). Then in chapter 7, Paul mentions, “This is my rule in all the churches” (1 Corinthians 7:17). On not being contentious, Paul adds, “We have no such practice, nor do the churches of God” (1 Corinthians 11:16). In 1 Corinthians 14:33, Paul again emphasizes that what he teaches is the practice everywhere. Finally, Paul explains that he also told the churches in Galatia about “the collection for the saints” (1 Corinthians 16:1; Galatians 2:10).

Paul clearly presents his teaching as universal. This in itself provides the justification to read Paul’s letters in light of one another. If Paul thinks about his teaching as one, then it follows that one can learn about this teaching from all his letters. However, although in 1 Corinthians Paul and Timothy tell us about the unity of teaching in all the churches, there is no sense yet that the various letters would be used as a unit, and Paul does not refer explicitly to other letters he wrote.

The first encouragement to read letters written to other churches appears in Colossians 4:16, written five to ten years after 1 Corinthians. In this Prison Letter, Paul actively encourages the Colossians to read the letter to the Laodiceans and vice versa. Though this second letter has not been preserved, Paul assumes the unity of teaching and the usefulness of reading a different explanation of the same doctrine. However, part of Paul’s intention in encouraging the exchange of letters is to foster fellowship between the two churches. After all, he could have included a copy of the Laodicean letter with the one to Colossae.

Interestingly, it is in Colossians that Paul mentions the struggle he has for those who have not seen him face to face (Colossians 2:1). This struggle, combined with Paul’s imprisonment and expectation of a possible execution, may have combined in Paul’s mind to think about his letters, and perhaps even a letter collection, as a way to encourage hearts and foster rich understanding of Christ for the many people he would never visit (Colossians 2:2–3).

Witness of 2 Peter

What Paul only suggested to the Colossians comes to full realization by the time Peter writes his second letter. Peter is aware that he will soon pass away (2 Peter 1:13–14), and like Paul in Colossians, he has a burden that the believers will have full access to the truth after his death (2 Peter 1:15). And of course, this letter itself is part of the means by which Peter accomplishes this goal.

Peter and the Pauline Teaching

Toward the end of the letter, Peter makes a remark about the apparent delay of the return of Jesus. He encourages the church not to see this as a delay but rather as a sign of God’s patience, and this for salvation, which, he says, is exactly what “our beloved brother Paul also wrote” (2 Peter 3:15).

It is worthwhile to pay close attention to what Peter says in this passage.

Count the patience of our Lord as salvation, just as our beloved brother Paul also wrote to you according to the wisdom given him, as he does in all his letters when he speaks in them of these matters. There are some things in them that are hard to understand, which the ignorant and unstable twist to their own destruction, as they do the other Scriptures. (2 Peter 3:15–16)

God entrusted Peter with opening the gospel of the kingdom to the Gentiles (Acts 15:7). This area of ministry would become Paul’s calling. From Paul’s account of his Jerusalem visit in Galatians 2:7–9, it is clear that Peter extended “the right hand of fellowship” to Paul. In 2 Peter 3, Peter makes exactly the same point. He publicly affirms Paul as an apostle and teacher of the church, as can be learned from Paul’s letters.

In addition, Peter recognizes that Paul received specific wisdom with regard to the present time between the first and second coming of the Lord. That is, Paul teaches “according to the wisdom given him,” but the message is not different from what Peter teaches. Peter uses the words “just as” (kathōs) deliberately.

Third, note the little phrase “to you” in verse 15. Peter knew that Paul had written to the same people. But who are they? The introduction to 2 Peter is not helpful in geographical terms: “To those who have obtained a faith of equal standing with ours by the righteousness of our God and Savior Jesus Christ” (2 Peter 1:1). However, Peter says in 2 Peter 3:1 that this is the second letter he is writing “to you.” And that means that the addressees are the same as those of the first letter — namely, “those who are elect exiles of the Dispersion in Pontus, Galatia, Cappadocia, Asia, and Bithynia” (1 Peter 1:1).

Paul had written to at least three churches in this wide area: the Galatians, Ephesians, and Colossians (also the Laodiceans, but that letter did not become part of the corpus of Paul’s preserved letters). Among other topics, these letters cover the doctrine of justification, the teaching of the church as the body of Christ, and how the life of the believer is now hidden with Christ in God. All these topics are relevant to understanding why the ongoing patience of the Lord is to be regarded as salvation.

Fourth, in verse 16, Peter widens the scope of Paul’s letters beyond those written to his audience by saying, “as he does in all his letters.” Peter endorses Paul, wherever Paul speaks about these matters, as teaching the same message. Peter knew about these letters and clearly had access to them. Apparently, they had become a collection that could be distributed, and Peter recommends them to his audience. (Whether or not his audience already had access to all Paul’s letters is not clear.)

Furthermore, Peter was fully aware of the controversies around Paul’s teaching — “the ignorant and unstable twist” his writings and misrepresent his words. For Peter, this is not a reason to avoid Paul’s letters. Yes, Paul’s teaching is at times difficult, but Peter still endorses it because those who twist Paul’s teaching also twist the other Scriptures. Does Peter have the Old Testament in mind with the term “other Scriptures” (or “other writings”)? Possibly so. But we cannot exclude the fact that by the time Peter wrote this, other written parts of the New Testament had come into being that were regarded as falling under the category of “Scriptures.” The apostolic letters carry the authority of Jesus Christ and are therefore truly the word of God.

2 Peter Among the Epistles

Second Peter is most explicit in referring to diverse sources of divine teaching. Peter refers to the Old Testament, to the words spoken beforehand by the holy prophets, and to the commandment of Jesus that came by means of the apostles (2 Peter 3:2). He mentions his first letter (2 Peter 3:1) and the letters of Paul, both to Peter’s audience and to others. He refers to events that we find recorded in the four Gospels: the transfiguration (2 Peter 1:16–18; see, e.g., Mark 9:2–8) and the announcement regarding the manner of Peter’s death (2 Peter 1:14; John 21:18–19).

Of course, Peter did not need the Gospel accounts to refer to these events as he was himself present at the time. Yet he could refer to these occasions expecting that his audience had been taught about them. In 2 Peter, we find references to a large amount of the teaching of the New Testament and a sense that this teaching is now being entrusted to writing.

There is one remaining conundrum in 2 Peter, and that is the relationship between this letter and the letter of Jude. Second Peter 2 has close parallels with Jude, citing the same illustrations in the same order. Though differences exist, the similarities suggest some sort of relationship between the two. Scholars differ as to the direction of influence (did Jude influence Peter or the other way around?). It suffices here to say that, once again, 2 Peter demonstrates how closely this letter ties in to the other apostolic writings.

Reading the Letters Together

The apostles clearly knew about one another and one another’s letters. At no point do we get a denial of the fundamental unity of their teaching. Among the earliest letters, we find Paul placing emphasis on the unity he has with the apostles in Jerusalem (Galatians 2:9) and on the unity of his teaching in all the churches, as we saw above in 1 Corinthians. In 2 Peter, one of the final letters, we see a conscious writing down and gathering together of the apostles’ teaching so that, after their death, believers would have access to the apostolic words. How then does this help us read the various letters of the New Testament in light of one another?

It is hardly necessary to explain that if we have two letters to the same church, it is good to read the second in light of what was said in the first (1 and 2 Corinthians, 1 and 2 Thessalonians, 1 and 2 Timothy, 1 and 2 Peter). But these are not the only “paired” letters. For example, Romans and Galatians cover similar ground. In many ways, Romans expands the doctrine explained in Galatians. Even the general order of topics in Galatians 2:15–5:26 resembles that of Romans 1–8. For example, the single thought of Galatians 5:17, “to keep you from doing the things you want to do,” receives fuller expression in Romans 7:15–25.

A similar relationship exists between other letters. Though Ephesians reads as if it is less prompted by an external situation than Colossians, both frequently use similar phraseology. Colossians also has a link with the small letter to Philemon, which is still best seen as the commendation of a converted runaway slave back to his master. It is illuminating to read the private letter to Philemon in light of what Paul says about slaves and masters in the letter to the whole church at Colossae, and vice versa. We will learn more once we see and ponder the connections.

On a smaller scale, Peter teaches us to link the themes he has discussed with the teaching of Paul on the same subject. We are encouraged to compare Scripture with Scripture.

Apostolic Foundation

Scripture is ultimately the word of God, and because of the divine author behind the human authors, we should expect to find a deep underlying unity. Nothing of what we discussed above aims to take anything away from this. Yet, as he so often does, God worked out his plans and intentions through traceable historical situations. The bringing together of the correspondence of the apostles into the New Testament is an example of this. This process did not happen in some mysterious way in the long years after the death of the apostles. On the contrary, as we have seen, it was a topic clearly on their minds toward the end of their ministry.

Paul uses the image in Ephesians 2:20 of the church being “built on the foundation of the apostles and prophets.” He includes his fellow workers in the plural noun “apostles.” John echoes this image in Revelation 21:14, where he links the foundation of the new Jerusalem with “the twelve apostles of the Lamb.” Since the apostles were aware of the role and responsibility they had and acknowledge one another in their writings, we would do well to accept their combined teaching, reading each letter not just in isolation but also in light of all the teaching we have received.