Revelation 17:10

17:10 five have fallen; one is, and the other has not yet come, but whenever he does come, he must remain for only a brief time.

Revelation 20:3

20:3 The angel then threw him into the abyss and locked and sealed it so that he could not deceive the nations until the one thousand years were finished. (After these things he must be released for a brief period of time.)