When you think about it, Peter’s speech in Acts 2 at Pentecost is worth a close read. It was, after all, the first sermon by a Christian after the Holy Spirit had been poured forth on them; indeed, it is the first post-Resurrection sermon, and I suppose the first evangelical sermon we have, period, by anyone besides Jesus Himself. Moreover, it marks a new Peter — and Peter himself is of course an important figure in the New Testament, so it is valuable to be able to add this talk to his two epistles and his other words in Acts. Besides, I recently posted an item on this blogsite about Paul’s speech in Athens on the Areopagus, so I should give equal time to Peter.
First, let’s set the stage: Chapter 2 of Acts begins with a description of how, at Pentecost (a Jewish harvest festival that takes place fifty days after Passover), the disciples were all meeting together in Jerusalem. Suddenly the house they were in was filled with a noise from heaven “like a violent, rushing wind,” and “there appeared to them tongues as of fire distributing themselves, and they rested on each one of them.” And “they were all filled with the Holy Spirit and began to speak in other tongues, as the Spirit was giving them utterance.”
Somehow this commotion spills out into the streets, and a crowd gathers, wondering what’s going on. What’s more, the crowd includes Jews from all over the world, and each “each one [was] hearing them speak in his own language.” It is this crowd that Peter then addresses.
Here is the text of Peter’s speech (Acts 2:14-41; boldface text indicates quotations from the Old Testament; the bracketed numbers, also in boldface, were inserted by me and are referenced in my following discussion):
 14 … “Men of Judea and all you who live in Jerusalem, let this be known to you and give heed to my words.15 For these men are not drunk, as you suppose, for it is only the third hour of the day;
 16 but this is what was spoken of through the prophet Joel:
17 ‘And it shall be in the last days,’ God says,
‘That I will pour forth of My Spirit on all mankind;
And your sons and your daughters shall prophesy,
And your young men shall see visions,
And your old men shall dream dreams;
18 Even on My bondslaves, both men and women,
I will in those days pour forth of My Spirit
And they shall prophesy.
19 ‘And I will grant wonders in the sky above
And signs on the earth below,
Blood, and fire, and vapor of smoke.
20 ‘The sun will be turned into darkness
And the moon into blood,
Before the great and glorious day of the Lord shall come.
21 ‘And it shall be that everyone who calls on the name of the Lord will be saved.’
 22 “Men of Israel, listen to these words: Jesus the Nazarene, a man attested to you by God with miracles and wonders and signs which God performed through Him in your midst, just as you yourselves know— 23 this Man, delivered over by the predetermined plan and foreknowledge of God, you nailed to a cross by the hands of godless men and put Him to death.
 24 But God raised Him up again, putting an end to the agony of death, since it was impossible for Him to be held in its power.25 For David says of Him,
‘I saw the Lord always in my presence;
For He is at my right hand, so that I will not be shaken.
26 ‘Therefore my heart was glad and my tongue exulted;
Moreover my flesh also will live in hope;
27 Because You will not abandon my soul to Hades,
Nor allow Your Holy One to undergo decay.
28 ‘You have made known to me the ways of life;
You will make me full of gladness with Your presence.’
29 “Brethren, I may confidently say to you regarding the patriarch David that he both died and was buried, and his tomb is with us to this day. 30 And so, because he was a prophet and knew that God had sworn to him with an oath to seat one of his descendants on his throne, 31 he looked ahead and spoke of the resurrection of the Christ, that He was neither abandoned to Hades, nor did His flesh suffer decay. 32 This Jesus God raised up again, to which we are all witnesses.
 33 Therefore having been exalted to the right hand of God, and having received from the Father the promise of the Holy Spirit, He has poured forth this which you both see and hear. 34 For it was not David who ascended into heaven, but he himself says:
‘The Lord said to my Lord,
“Sit at My right hand,
35 Until I make Your enemies a footstool for Your feet.”’
36 Therefore let all the house of Israel know for certain that God has made Him both Lord and Christ—this Jesus whom you crucified.”
 37 Now when they heard this, they were pierced to the heart, and said to Peter and the rest of the apostles, “Brethren, what shall we do?” 38 Peter said to them, “Repent, and each of you be baptized in the name of Jesus Christ for the forgiveness of your sins; and you will receive the gift of the Holy Spirit. 39 For the promise is for you and your children and for all who are far off, as many as the Lord our God will call to Himself.” 40 And with many other words he solemnly testified and kept on exhorting them, saying, “Be saved from this perverse generation!” 41 So then, those who had received his word were baptized; and that day there were added about three thousand souls.
So, in a nutshell, Peter tells the crowd that what’s just happened here is an outpouring of the Holy Spirit; that this happened in turn because of the recent Crucifixion and Resurrection of Jesus Christ, our Lord; and that what is to be done now is repentance and baptism.
But let’s look more closely at how wonderfully Peter delivers this message.
In  — that is, verses 14 and 15 — Peter addresses the claim that all the unusual language is simply the result of too much wine, noting that it’s too early in the morning for them to be drunk. (I wonder if this is a joke, since it suggests that of course they might be drunk later on. Probably not, since Peter gets very serious very quickly; rather, he is saying that nobody gets drunk this early.)
Side note: I thought it was interesting that, in the NASB translation above, Peter addresses his words to “men of Judea and all you who live in Jerusalem”; you’d think he’d address it to “My fellow Jews,” given what follows and the likelihood that Peter knows the crowd includes non-Jerusalem Jews here for the Pentecost. Well, as it turns out, there are some differences in translation and indeed apparently in some of the manuscripts themselves, so some Bibles have the broader language.
As just indicated, the Jewish festival of Pentecost brought Jews from many countries to Jerusalem. There was plenty of opportunity, then, for foreign languages to be spoken; what’s more, there was also the opportunity here for the Gospel to be taken back to a wide variety of places, as presumably happened after Peter’s dramatic address.
In , Peter quotes from Joel 2:28-32. Peter introduces this quotation by saying it will explain what’s going on that morning, so the most immediately salient part of Joel would be the references in the first two verses there to the Spirit being poured out.
Peter could have stopped at verse 18 (which ends the Spirit part) but he goes on to more prophecy. Perhaps, if the recent eclipse that had taken place on Good Friday was still on people’s minds, Joel’s reference to the sun being turned into darkness would get people’s attention, and the same if there had been a recent blood-red moon, and so forth. And, very significantly to what follows, Peter doesn’t stop until he has recited this verse from Joel: “And it shall be that everyone who calls on the name of the Lord will be saved.”
So Peter, in this first evangelical sermon, is setting two important precedents. First, he shows how Christianity is rooted in what’s observable and true in the world. Second, he shows how Christianity fulfills Old Testament prophecy. Both have been a part of Christian apologetics ever since.
Then, in , Peter suddenly starts talking about a certain Nazarene. He aims to confront the Jews with the reality of who Jesus Christ was. He does not mince any words, telling them, “[Y]ou nailed [Him] to a cross by the hands of godless men and put Him to death.” But neither does he dwell on this, because his point is not to condemn the Jews for their role in the Roman crucifixion but to tell them what they have the opportunity to do now.
And so, in , Peter now uses Old Testament prophecy again for his Jewish audience, this time for the purpose of explaining who Jesus Christ was. He quotes David, no less (Psalm 16:8-11), and explains how he foretold the Resurrection.
And then, in , Peter brings the Holy Spirit — what he was talking about before — back into the discussion. The way he weaves all these threads together is really quite skillful. Not bad for an impromptu sermon by a fisherman who, not long ago, had cowardly denied Jesus. It is, as I said earlier, a new Peter we now see. Peter concludes by declaring that the resurrected Jesus is none other than the Lord — once again, he quotes David, this time Psalm 110:1 — and now reminds the Jewish audience again that it is He “whom you crucified.”
But wait: There’s more! Peter no doubt anticipated that the note he ended on would provoke a reaction from the crowd. Sure enough, in  there’s a first-century version of a Q-and-A session after Peter’s speech, with the Q being, “Uh oh, so what are we supposed to do now?” Peter gives the A: “Repent and be baptized.” It turns out that the news Peter has for the Jews is not bad after all, but very good: They can all be saved, they can all be forgiven, they can all receive the gift of the Holy Spirit that they have seen poured out before them that day.
And thousands in that audience took Peter’s words to heart and came to Christ.
One additional note: It’s interesting that what happened at Pentecost reverses what happened in Genesis 11:1-9 with the Tower of Babel. Instead of God, presumably through the Holy Spirit, making it impossible for people who had been speaking the same language to understand each other at all because now they had different tongues, here the Holy Spirit makes it possible for humans who had been speaking different languages to understand each other perfectly well.
Thus, Christ’s message is to be universal, brought to all people. And, as noted above, the fact that Pentecost brought Jews to Jerusalem from all over the world meant that, after the pouring out of the Holy Spirit and Peter’s sermon about it, there was now the opportunity for the Gospel to be spread far and wide when these Jews returned home.