Acts 1:1-3

1:1 In my former book, Theophilus, I wrote about all that Jesus began to do and to teach

1:2 until the day he was taken up to heaven, after giving instructions through the Holy Spirit to the apostles he had chosen.

1:3 After his suffering, he presented himself to them and gave many convincing proofs that he was alive. He appeared to them over a period of forty days and spoke about the kingdom of God.