When you think about it, the complementarity of the early church leaders was interesting, and its dynamics must have been, too. So is the fact that each of them authored Scripture.
Regarding the interplay of personalities and backgrounds, think in particular of Peter, Paul, and James — a group that can, I think, be fairly characterized as the Big Three of the early church leadership.
Peter was a fisherman by trade, joined Jesus at the beginning of His ministry, and was extremely close to Him. James, who was Jesus’ brother, grew up with Him in the backwater town of Nazareth and presumably knew Him well, too — but was not one of His followers until later, and indeed maybe not until after the Crucifixion. And Paul, who was by far the best educated of the three and was born in the metropolis of Tarsus and grew up in Jerusalem, did not know Jesus at all before the Crucifixion and was in fact a persecutor of Christians until Jesus appeared to him on the road to Damascus. But all three became church leaders and died martyrs.
Imagine, then, what interactions among the three of them must have been like. James was Jesus’ brother, but Peter had followed Him the longest and most loyally, and Paul was the smartest. On the other hand, Paul was the latest to the party and indeed had been the most hostile, Peter was the least sophisticated and behaved shamefully once Jesus was arrested, and James had in some ways been the most disloyal, disbelieving and failing to follow his own brother.
Now, in some contexts, this divergence might have been a source of division, but I don’t think it would have been here. That’s because the Great Big Thing all three had in common must have overwhelmed, must have trivialized, their differences. They had, each of them, come to know the One True God, and it was they and their embattled few followers who were now, together, going to transform and save the whole world.
Instead, they must have eagerly welcomed each other’s talents and insights, applauded one another’s bravery — for all were physically brave men — pulled for each other, prayed for each other.
P.S. Note that Paul’s protege Luke wrote the book of Acts, which is as positive about Peter as it is about Paul. Indeed, without Luke’s account of the post-Resurrection Peter in Acts, we would have a much lower opinion of him. I think this suggests a lack of back-biting among the two apostles.
Regarding the role each of the three had in writing Scripture, note first that, in many endeavors, leadership does not always go with authorship. We read today what Julius Caesar and Marcus Aurelius wrote, but do we read anything by any other Roman ruler over the half millennium stretching from 44 B.C. to A.D. 476? Only, perhaps, Julian the Apostate in some limited circles.
On the other hand, the challenges facing the leaders of the early church were of a different sort than faced Roman rulers, and we can feel blessed to have some of the thoughts they had as they faced those challenges. One wonders of there was more written by them than we have.
Still, we have two letters Peter authored and, via John Mark, one of the Gospels; James wrote an important letter; and of course Paul wrote many letters (and his protege Luke wrote one of the Gospels as well as Acts).
John was another early church leader (see, e.g., Galatians 2:9, where Paul refers to him, along with James and Peter, as “pillars of the church”), and — next to Paul and Luke — authored the most Scripture. He also had an interesting background, although I will not dwell on it too much since it’s unclear which John wrote which book.
The other key church leader was apparently Barnabas, and I’ve noted elsewhere that it would be nice if, as is possible, he was the author of Hebrews so we could be hearing from him, too.
And the remaining New Testament authors are Matthew and Jude. I think it is fair to say that both of them are relatively obscure individuals historically. Indeed, when the authors all got together, they playfully nicknamed the latter “Jude the Obscure.” (Just kidding!) And I’ve noted that, as for the former, “[New Testament scholar Richard] Bauckham suggests that the author of Matthew, while intending to present Matthew’s perspective, was not himself Matthew (108-12).” That would make him even more obscure.
Now, I have written elsewhere on this blogsite about the complementarity of the Gospels’ authorship:
I’ll note that, if [the author of John was not the apostle John but another disciple by that name], there is a pleasing (providential?) complementarity among the Gospels. We have one from the perspective of the leading apostle (Mark, who presents Peter’s account), one from another but much less prominent apostle (Matthew), one from a close disciple who was not one of the twelve but represents a different, Jerusalem-based following (John), and another from a Gentile/Pauline view (Luke). What else could we ask for?
The same sort of variety is found in the rest of the New Testament. It is authored by a mix of intellectuals and nonintellectuals, Jews and Gentiles, Jerusalem-based and non-Jerusalem-based Jews, and the relatively well-known and the more obscure.
Is there any conclusion to be drawn from this? I don’t think God believes in affirmative-action quotas, so I think the diversity here simply underscores the universality and plausibility of the Message — that all peoples can be saved and inspired — and makes it much harder to claim that Scripture was written through some hidden and secret conspiracy.