Acts 1:1-5 - The Preface
1 My first account, O Theophilus, dealt with all that Jesus began doing and teaching from the beginning down to the day when, 2 after giving instructions through the Spirit to the apostles whom he had chosen, he was taken up to heaven. 3 After his sufferings he had also shown himself alive to them in many convincing manifestations, revealing himself to them during forty days, and speaking of the kingdom of God.
4 And once when he was eating with them he charged them not to depart from Jerusalem, but to wait for the promise of the Father. "Of this," he said, "you have heard from me. 5 "For John indeed baptized in water, but you shall be baptized in the Holy Spirit not many days hence."