2 Chronicles 20:3 in the King James Version
And Jehoshaphat feared, and set himself to seek the LORD, and proclaimed a fast throughout all Judah.
Context
2 Then some came who told Jehoshaphat, saying, “A great multitude is coming against you from beyond the sea from Syria. Behold, they are in Hazazon Tamar” (that is, En Gedi).
3 Jehoshaphat was alarmed, and set himself to seek the LORD. He proclaimed a fast throughout all Judah.
4 Judah gathered themselves together to seek help from the LORD. They came out of all the cities of Judah to seek the LORD.