Remember the Gospels and Acts were composed AFTER Paul's letters.
Gerd Lüdemann:
"Not once does Paul refer to Jesus as a teacher, to his words as teaching, or to [any] Christians as disciples."
"Moreover, when Paul himself summarizes the content of his missionary preaching in Corinth (1 Cor. 2.1-2; 15.3-5), there is no hint that a narration of Jesus’ earthly life or a report of his earthly teachings was an essential part of it. . . . In the letter to the Romans, which cannot presuppose the apostle’s missionary preaching and in which he attempts to summarize its main points, we find not a single direct citation of Jesus’ teaching."
According to Richard Carrier, Paul's letters indicate that Cephas etc. only knew Jesus from DREAMS, based on the Old Testament scriptures.
1 Cor. 15.:
"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."
The Scriptures Paul is referring to here are:
Septuagint version of Zechariah 3 and 6 gives the exact Greek name of Jesus, describing him as confronting Satan, being crowned king in heaven, called "the man named 'Rising'" who is said to rise from his place below, building up God’s house, given supreme authority over God’s domain and ending all sins in a single day.
Daniel 9 describes a messiah dying before the end of the world.
Isaiah 52-53 describes the cleansing of the world's sins by the death of a servant.
