In a Synagogue in Antioch of Pisidia (middle of Turkey) Paul was invited to present a word of exhortation. When he stood to do so, out of his mouth came a marvelous presentation of the Gospel of Jesus (God's good news to Israel).
He sketches out how God fulfilled the two great Promises: one to Abraham and one to David. These were the foundation of Israel's hope; and in them, the hope of glory for the Gentiles as well.
One thing to specially note is how often Paul connects the message about Jesus to "this people Israel."
Also note: the similarities between Paul's message and the warnings of the prophets regarding the earlier fall of Jerusalem. Only those who followed the voice of God's prophet escaped the first time; so it will be in Paul's case.