This is Acts 3:11-21:

11 While he clung to Peter and John, all the people, utterly astounded, ran together to them in the portico called Solomon's. 12 And when Peter saw it he addressed the people: "Men of Israel, why do you wonder at this, or why do you stare at us, as though by our own power or piety we have made him walk? 13 The God of Abraham, the God of Isaac, and the God of Jacob, the God of our fathers, glorified his servant Jesus, whom you delivered over and denied in the presence of Pilate, when he had decided to release him. 14 But you denied the Holy and Righteous One, and asked for a murderer to be granted to you, 15 and you killed the Author of life, whom God raised from the dead. To this we are witnesses. 16 And his name—by faith in his name—has made this man strong whom you see and know, and the faith that is through Jesus has given the man this perfect health in the presence of you all.
17 "And now, brothers, I know that you acted in ignorance, as did also your rulers. 18 But what God foretold by the mouth of all the prophets, that his Christ would suffer, he thus fulfilled. 19 Repent therefore, and turn back, that your sins may be blotted out, 20 that times of refreshing may come from the presence of the Lord, and that he may send the Christ appointed for you, Jesus, 21 whom heaven must receive until the time for restoring all the things about which God spoke by the mouth of his holy prophets long ago.

Well, what comes next in the passage we're looking at is like a lesson, an instructional manual on how to preach the gospel, whether we're doing that publicly or we're doing that in private. I think the first sermon I ever preached was on the street in Columbia, South Carolina. I was passing out gospel literature to soldiers who were about ready to go to Vietnam, and one soldier asked me a question very loudly, and as he asked that question, a bunch of soldiers gathered. I ended up standing up on a park bench and more and more soldiers gathered, and I just ended up preaching to this group of soldiers until military police came along and told me I couldn't block the street. I didn't have any idea what preaching was about. But we get this instruction here in Acts.

First thing that Peter and John teach us is, don't start with John 3:16; start with Genesis. Start with God's existence and God's covenantal plan because that's the only thing that makes sense. If there is no God, and he does not care about his world, then the gospel has no meaning. So you have to start there.

Second thing, you have to preach human responsibility. You have to talk about lives of denial and rejection of God even though there's evidence. You see, this is the logic of gospel preaching. If you don't hear the bad news, the good news doesn't mean anything to you. If there's not something that I should be concerned about and afraid of that's inside of me, why would I care what you have to say to me?

Third thing, call people to repentance. Call people to action; call people to respond. Don't just leave the message hanging out there. Response is important and that invitation is important.

Fourth, comfort people with God's promise of forgiveness and cleansing, that this God, when they come to him, is no longer their judge. He's their Father, and he will do for them what they can't do for themselves, not only to forgive them, but to cleanse their hearts.

Fifth, point people to the gift of God's ongoing presence and grace. Peter talks about that in "times of refreshing." God is now present with you; he comes to live inside of you, and he is for you and in you and with you. You now live with the presence of God.

And the sixth thing, make sure you let people know that, as now a child of God, their destiny is secure. All things will be restored! This groaning world that's waiting for redemption will be restored. There will be a new heaven and new earth where peace and righteousness will reign forever and ever, and they will be there in that world where there's no suffering and no sin anymore!

Now maybe you won't do this all at once, but these principal elements of gospel preaching and witness must be in our gospel preaching and gospel witness. And when we faithfully witness, God graciously saves. That's beautiful! When we faithfully witness, God graciously saves!