But when God, who had set me apart even from my mother's womb and called me through His grace, was pleased to reveal His Son in me so that I might preach Him among the Gentiles, I did not immediately consult with flesh and blood, nor did I go up to Jerusalem to those who were apostles before me; but I went away to Arabia, and returned once more to Damascus. Then three years later I went up to Jerusalem to become acquainted with Cephas, and stayed with him fifteen days. But I did not see any other of the apostles except James, the Lord's brother.
Paul doesn't say what he and Cephas talked about, but many Christian apologists think that Cephas gave Paul the creed that is found in 1 Corinthians 15:3-8.
For I delivered to you as of first importance what I also received, that Christ died for our sins according to the Scriptures, and that He was buried, and that He was raised on the third day according to the Scriptures, and that He appeared to Cephas, then to the twelve. After that He appeared to more than five hundred brethren at one time, most of whom remain until now, but some have fallen asleep; then He appeared to James, then to all the apostles; and last of all, as to one untimely born, He appeared to me also.I do not personally find this argument persuasive. When Paul says that he delivered what he received, I think he is talking about the message of salvation that he received by revelation from God, not a particular creedal formulation of that message that he received from Cephas. I think this is consistent with the way Paul uses the word "received" in other places. I think that Paul would have known the elements of the creed before he went to Jerusalem since he had already been preaching for three years, but I don't think we have any evidence of when or where those elements were put into the particular creed found in 1 Corinthians 15.
Many people do not share my reservations about the apologists arguments. I frequently come across people who assert that Paul got the creed when he visited Jerusalem as if it was an incontrovertible fact. When I point out the fact that Paul never says this, they will cite apologists like William Lane Craig or Gary Habermas or they will simply assert that it is the consensus position of biblical scholars. I think that mostly they accept it because it "makes sense" that Paul learned the creed on his first visit to Jerusalem.
I think this is probably a very good illustration of the way that the stories in the gospels may have grown over time. When people pass along stories, they add details that make sense and those details are accepted as part of the story. In our literate culture, it is possible to look at what Paul actually wrote, but that doesn't prevent people from accepting added details as facts. In an oral culture, there would be no way to determine which details in a story were original and which had been added in the retelling because they made sense.
It is very easy to imagine how details could be added incrementally to create a story. For example, Paul never says anything about the empty tomb or how Jesus was buried in any of his letters. For all we know, Paul might have believed that the Romans had thrown Jesus' body into a common grave for executed criminals. However, it would have made sense that Jesus' body was no longer in the grave because Paul said that Jesus was physically resurrected. Someone who was retelling the story of the appearances that he heard from Paul might simply have added the empty tomb. Once you've got the empty tomb in the story, it would have made sense that someone had seen it empty. In order for someone to find the tomb empty, it must have been a specific tomb rather than a common grave. In order for a crucified criminal to receive an honorable burial, it makes sense that there would have been a prominent person who had some political pull but was nonetheless sympathetic to Jesus. Before you know it, you have the story of Joseph of Arimathea.
It fascinates me that Bible believers can so easily accept as fact the content of Paul's conversations on his visit to Jerusalem when it fits the narrative that they want to believe, but they recoil in such horror at the notion that the stories recorded in the gospels might be the product of a similar series of embellishments.