Acts 2:1-41

Finally the day of Pentecost arrived. Jews from all over would come to Jerusalem several times a year to observe festivals. God chose one of those festivals to pour out his Spirit and to birth the church.

For the past ten days this group of 120 had been together, devoting themselves to prayer. All they knew was that Jesus had told them to return to Jerusalem and wait. On the morning of Pentecost, while the city was crammed with people from all over, the Holy Spirit fell on the followers of Jesus and they began praising God in languages that they did not know. Others knew these languages, though. They were the languages of the devout Jews who had traveled from all over the known world to come to Jerusalem.

A large crowd gathered. A few onlookers were skeptical, believing that they were drunk. However, most were amazed by what was taking place. Peter stood up along with the eleven other apostles, and he addressed the crowd. Before going any farther, I have to go back in time. This is the Peter who constantly spoke up before thinking. He's the one who on one hand speaks up and declares that Jesus is the Messiah, but then soon afterwards rebukes Jesus when he says that he is going to die soon. He's the one denies Jesus after arguing with Jesus that denial was impossible. And he is the one whom Jesus restored. That Peter gets up and addresses the crowd.

He quotes from the prophet Joel. Everyone in the crowd surely knows this passage of Scripture. In that passage God declared that he would pour out his Spirit on his people. Peter then transforms into a bold preacher. He points to Jesus as the fulfillment of all of Scripture. And he tells the crowd that it was they who murdered him.

I think the key statement, the tipping point, so to speak, was when Peter said, "Let all the house of Israel therefore know for certain that God has made him both Lord and Christ, this Jesus whom you crucified."

Later on in the book of Acts, Paul makes statements like this and then is stoned or run out of town. But this is not what happens at this moment. Those who heard Peter "were cut to the heart", and their response was, "Brothers, what shall we do?" (2:37). Peter's response:
Repent and be baptized every one of you in the name of Jesus Christ for the
forgiveness of your sins, and you will receive the gift of the Holy Spirit (2:38).

What an amazing day! After Peter's sermon, 3000 people believed, were baptized, and became a part of a dynamic new community that would later be known as the Church.