Acts 1:7-12 NIV
He said to them: “It is not for you to know the times or dates the Father has set by his own authority. But you will receive power when the Holy Spirit comes on you; and you will be my witnesses in Jerusalem, and in all Judea and Samaria, and to the ends of the earth.”
After he said this, he was taken up before their very eyes, and a cloud hid him from their sight.
They were looking intently up into the sky as he was going, when suddenly two men dressed in white stood beside them. “Men of Galilee,” they said, “why do you stand here looking into the sky? This same Jesus, who has been taken from you into heaven, will come back in the same way you have seen him go into heaven.”
Then the apostles returned to Jerusalem from the hill called the Mount of Olives, a Sabbath day’s walk from the city.
NIV: New International Version