Revelation 20:1-3

1Then I saw an angel coming down from heaven with the key to the bottomless pit and a heavy chain in his hand.

2He seized the dragon—that old serpent, who is the devil, Satan—and bound him in chains for a thousand years.

3The angel threw him into the bottomless pit, which he then shut and locked so Satan could not deceive the nations anymore until the thousand years were finished. Afterward he must be released for a little while.