Where do you first hear the phrase "repent and be baptized" in the Bible?

Les explains that when he asks where people first hear "repent and be baptized," the answer is John the Baptist. John's ministry was not to Gentiles but only to the covenant people of Israel. They were to repent and be baptized in preparation for the coming of their King, so they could be a nation of priests to take the knowledge of their God to pagan Gentiles. Later, in the same chapter, verse 38 is tied to verse 36: all the house of Israel is told that God made Jesus both Lord and Christ, and they were to repent and be baptized. Les stresses this was still only for the nation of Israel, and he warns against reading other ideas into it.