How did the early church flourish?
They didn’t have the Gospels or any of the epistles written until about 50-69 AD. The Jews had the OT scriptures and prophesies to verify that Jesus was the Messiah. The Gentiles had nothing to look back on. They had no historical records, or prophesies. They were “without hope and without God in the world” and yet they had part in His Kingdom written in the OT. “A light to lighten the Gentiles “, and “in thee will the Gentiles Trust”. But they didn’t know that.