2 Chronicles 20:15

15 He said, “Listen, all you people of Judah and Jerusalem! Listen, King Jehoshaphat! This is what the LORD says: Do not be afraid! Don’t be discouraged by this mighty army, for the battle is not yours, but God’s.

2 Chronicles 20:15 Meaning and Commentary

2 Chronicles 20:15

And he said, hearken ye, all Judah, and ye inhabitants of
Jerusalem, and thou King Jehoshaphat
There is a climax or gradation in these words rising from the lowest to the highest; from the people of the cities in the country, to the inhabitants of Jerusalem the metropolis, and from thence to the king the supreme governor: thus saith the Lord unto you, be not afraid, nor dismayed, by reason of
this great multitude;
whose numbers were discouraging to the king, and he had taken notice of them, which this respects: for the battle is not your's, but God's:
the cause was his, and he would espouse and maintain it; not they, but he, would fight the battle, and therefore they had nothing to fear.

2 Chronicles 20:15 In-Context

13 As all the men of Judah stood before the LORD with their little ones, wives, and children,

14 the Spirit of the LORD came upon one of the men standing there. His name was Jahaziel son of Zechariah, son of Benaiah, son of Jeiel, son of Mattaniah, a Levite who was a descendant of Asaph.

15 He said, “Listen, all you people of Judah and Jerusalem! Listen, King Jehoshaphat! This is what the LORD says: Do not be afraid! Don’t be discouraged by this mighty army, for the battle is not yours, but God’s.

16 Tomorrow, march out against them. You will find them coming up through the ascent of Ziz at the end of the valley that opens into the wilderness of Jeruel.

17 But you will not even need to fight. Take your positions; then stand still and watch the LORD ’s victory. He is with you, O people of Judah and Jerusalem. Do not be afraid or discouraged. Go out against them tomorrow, for the LORD is with you!”