So Paul stood up and with a gesture began to speak: “You Israelites, and others who fear God, listen. The God of this people Israel chose our ancestors and made the people great during their stay in the land of Egypt, and with uplifted arm he led them out of it. For about forty years he put up with them in the wilderness. After he had destroyed seven nations in the land of Canaan, he gave them their land as an inheritance for about four hundred fifty years. After that he gave them judges until the time of the prophet Samuel. Then they asked for a king; and God gave them Saul son of Kish, a man of the tribe of Benjamin, who reigned for forty years. When he had removed him, he made David their king. In his testimony about him he said, ‘I have found David, son of Jesse, to be a man after my heart, who will carry out all my wishes.’ Of this man’s posterity God has brought to Israel a Savior, Jesus, as he promised; before his coming John had already proclaimed a baptism of repentance to all the people of Israel. And as John was finishing his work, he said, ‘What do you suppose that I am? I am not he. No, but one is coming after me; I am not worthy to untie the thong of the sandals on his feet.’ “My brothers, you descendants of Abraham’s family, and others who fear God, to us the message of this salvation has been sent. Because the residents of Jerusalem and their leaders did not recognize him or understand the words of the prophets that are read every sabbath, they fulfilled those words by condemning him. Even though they found no cause for a sentence of death, they asked Pilate to have him killed. When they had carried out everything that was written about him, they took him down from the tree and laid him in a tomb. But God raised him from the dead; and for many days he appeared to those who came up with him from Galilee to Jerusalem, and they are now his witnesses to the people. And we bring you the good news that what God promised to our ancestors he has fulfilled for us, their children, by raising Jesus; as also it is written in the second psalm, ‘You are my Son; today I have begotten you.’ As to his raising him from the dead, no more to return to corruption, he has spoken in this way, ‘I will give you the holy promises made to David.’ Therefore he has also said in another psalm, ‘You will not let your Holy One experience corruption.’ For David, after he had served the purpose of God in his own generation, died, was laid beside his ancestors, and experienced corruption; but he whom God raised up experienced no corruption. Let it be known to you therefore, my brothers, that through this man forgiveness of sins is proclaimed to you; by this Jesus everyone who believes is set free from all those sins from which you could not be freed by the law of Moses. (Acts 13:16-39, NRSV)
Paul gives us the readers digest history of Christianity here.
He tells us and those present how we have gotten to this point, and that the message was there all along. This is not a new message, that God wants us to turn around and follow Him. He has been telling us this all along. So follow after Jesus, and allow His life to permeate your life.