The first account I composed, Theophilus, about all that Jesus began to do and teach, until the day when He was taken up to heaven, after He had by the Holy Spirit given orders to the apostles whom He had chosen. To these He also presented Himself alive after His suffering, by many convincing proofs, appearing to them over a period of forty days and speaking of the things concerning the kingdom of God. Gathering them together, He commanded them not to leave Jerusalem, but to wait for what the Father had promised, “Which,” He said, “you heard of from Me; for John baptized with water, but you will be baptized with the Holy Spirit not many days from now.”
So when they had come together, they were asking Him, saying, “Lord, is it at this time You are restoring the kingdom to Israel?” He said to them, “It is not for you to know times or epochs which the Father has fixed by His own authority; but you will receive power when the Holy Spirit has come upon you; and you shall be My witnesses both in Jerusalem, and in all Judea and Samaria, and even to the remotest part of the earth.”
And after He had said these things, He was lifted up while they were looking on, and a cloud received Him out of their sight. And as they were gazing intently into the sky while He was going, behold, two men in white clothing stood beside them. They also said, “Men of Galilee, why do you stand looking into the sky? This Jesus, who has been taken up from you into heaven, will come in just the same way as you have watched Him go into heaven.”