Here in Acts 2 we read about the very first Christian sermon that was preached.  It was a sermon preached by Peter on the day of Pentecost.  We all know that Peter was an imperfect vessel, yet the words of his sermon contained in this text are far from imperfect because they are the very words of God Himself preserved in inspired and inerrant Scripture.  Peter wasn’t perfect, yet he was used to preach the gospel on the day of Pentecost, and 3,000 people were saved. The first event of church history that followed the coming of the Holy Spirit was Peter’s sermon at Pentecost whereby the church was launched.