James F. McGrath, The A to Z of the New Testament: Things Experts Know That Everyone Else Should Too (Eerdmans, 2023), 206-207.
It is important to get away from two inaccurate ideas about the way the canon formed. One bit of misinformation that was popularized in Dan Brown’s The Da Vinci Code is that the emperor Constantine gathered bishops at the Council of Nicaea and told them they had too many gospels and should settle on four. In actual fact, the canon was not even a focus at the Council of Nicaea. The second inaccurate idea is that some people think the table of contents for the New Testament simply dropped down from heaven. But the table of contents in a Bible is not itself part of the canon. In reality, the process of canon formation was at once much simpler and much messier than these two popular scenarios envisage. The core of the New Testament emerged as a result of the sharing of literature among churches connected in a network that naturally developed as the gospel spread and communities formed. The works that were most widely accepted became canonical. Ones that were not as widely known either caught on or were eventually excluded. Debates about what constitutes scripture occurred throughout, but there was also a core collection of gospels and letters of Paul that took shape organically.
The Amateur Exegete 