'Coming on the Clouds' in the Bible

and then the sign of the Son of Man will appear in the sky. Then all the tribes of the earth will mourn, and they will see the Son of Man coming on the clouds of the sky with power and great glory.

Jesus said to him, "You have said it. Nevertheless, I tell you, after this you will see the Son of Man sitting at the right hand of Power, and coming on the clouds of the sky."