Joel 2:31-32

31The sun will be turned to darkness and the moon to blood before the coming of the great and dreadful day of the LORD . 32And everyone who calls on the name of the LORD will be saved; for on Mount Zion and in Jerusalem there will be deliverance, as the LORD has said, even among the survivors whom the LORD calls. In Hebrew texts 2:28-32 is numbered 3:1-5.