2 Chronicles 20:3, 12, 15, 22, 30

Then Jehoshaphat was afraid and set himself [determinedly, as his vital need] to seek the LORD; and he proclaimed a fast throughout all Judah.

O our God, will You not judge them? For we are powerless against this great multitude which is coming against us. We do not know what to do, but our eyes are on You.”

He said, “Listen carefully, all [you people of] Judah, and you inhabitants of Jerusalem, and King Jehoshaphat. The LORD says this to you: ‘Be not afraid or dismayed at this great multitude, for the battle is not yours, but God’s.

When they began singing and praising, the LORD set ambushes against the sons of Ammon, Moab, and Mount Seir, who had come against Judah; so they were struck down [in defeat].

So the kingdom of Jehoshaphat was quiet, for his God gave him rest on all sides.