Acts 1:2-3

1:2 until the day he was taken up to heaven, after he had given orders by the Holy Spirit to the apostles he had chosen. 1:3 To the same apostles also, after his suffering, he presented himself alive with many convincing proofs. He was seen by them over a forty-day period and spoke about matters concerning the kingdom of God.

Acts 1:22

1:22 beginning from his baptism by John until the day he was taken up from us – one of these must become a witness of his resurrection together with us.”