And when he had spoken these things, while they beheld, he was taken up; and a cloud received him out of their sight.
All Commentaries on Acts 1:9 Go To Acts 1
John Chrysostom
AD 407
This too was a sure sign that He went up to Heaven. Not fire, as in the case of Elijah, nor fiery chariot, but a cloud received Him; which was a symbol of Heaven, as the Prophet says; Who makes the clouds His chariot Psalm 104:3.