Joel 2:31 in the King James Version
The sun shall be turned into darkness, and the moon into blood, before the great and the terrible day of the LORD come.
Context
30 I will show wonders in the heavens and on the earth: blood, fire, and pillars of smoke.
31 The sun will be turned into darkness, and the moon into blood, before the great and terrible day of the LORD comes.
32 It will happen that whoever will call on the LORD’s name shall be saved; for in Mount Zion and in Jerusalem there will be those who escape, as the LORD has said, and among the remnant, those whom the LORD calls.