Thank you for the question on the writing of the Synoptic Gospels and Acts, “Do you think it is logical to think that the synoptic Gospels and Acts were written before the Temple was destroyed?”
As the news about the words and works of Jesus spread from mouth to mouth, there were living witnesses who heard and saw Jesus and the Apostles. There were the Jewish leaders, the Apostles, the common people who heard the words and saw the works of Jesus as the Sermon on the Mount or the Olivet Discourse.
Dr. Luke states in his Gospel that many have undertaken to draw up an account of the things that have been fulfilled among us, just as they were handed down to us by those who from the first eyewitnesses an servants of the word (Luke 1:1–2). This writing down of eyewitnesses of the events surrounding Jesus were written down. It is likely that the accounts written by others were incomplete or inaccurate to some extent. Luke further writes that he investigated that what he has written is true and accurate.
It is reasonable to think that as the Good News of salvation spread to the Gentiles that the Gentiles would like to know more about the life of Jesus. The Gospels of Matthew, Mark, and Luke are the records of eyewitnesses or recording of what the Apostles wrote or dictated to their writers. This became even more paramount with the destruction of the Temple in 70 CE, the aging or death of witnesses, the scattering of the Jews and the deaths of the Apostle. The written records of their testimony by the Apostles were treasured by the Gentiles and the scattered Jews. There were probably other writings as the Gospel of Thomas or Barnabas, but those writings were not viewed by church leaders as being true to the testimony of Jesus and the Apostles. The early church read them in their midst while some leaders believe they were canonical while others felt those writings should not be part of the canon of Scripture.
SUMMARY: It is reasonable with the passing of time that written records of the words and works of Jesus would be written down.
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