The Catechism in Questions & Answers

190. What happened at the ascension of Jesus Christ?

Forty days after His resurrection, Jesus Christ ascended into heaven. There are eyewitnesses to this event. After He had spoken to His Apostles and blessed them, He was taken up into heaven, and a cloud received Him out of their sight. As they looked into heaven after Him, two angels stood beside them and said: “This same Jesus, who was taken up from you into heaven, will so come in like manner as you saw Him go into heaven” (Acts 1: 11).

“I came forth from the Father and have come into the world. Again, I leave the world and go to the Father.”
John 16: 28