Joel 2:9-12

9They shall run to and fro in the city; they shall run upon the wall, they shall climb up upon the houses; they shall enter in at the windows like a thief. 10The earth shall quake before them; the heavens shall tremble: the sun and the moon shall be dark, and the stars shall withdraw their shining: 11And the Lord shall utter his voice before his army: for his camp is very great: for he is strong that executeth his word: for the day of the Lord is great and very terrible; and who can abide it?

12Therefore also now, saith the Lord, turn ye even to me with all your heart, and with fasting, and with weeping, and with mourning: