Charles Spurgeon Commentary 2 Chronicles 20:15-17

"and he said, Hearken ye, all Judah, and ye inhabitants of Jerusalem, and thou king Jehoshaphat: Thus saith Jehovah unto you, Fear not ye, neither be dismayed by reason of this great multitude; for the battle is not yours, but God`s. To-morrow go ye down against them: behold, they come up by the ascent of Ziz; and ye shall find them at the end of the valley, before the wilderness of Jeruel. Ye shall not need to fight in this [battle]: set yourselves, stand ye still, and see the salvation of Jehovah with you, O Judah and Jerusalem; fear not, nor be dismayed: to-morrow go out against them: for Jehovah is with you." — 2 Chronicles 20:15-17 (ASV)

Oh, how those words must have fallen on the weary ears of those who were in such trouble! And how glad those ears must have been to hear such a message of wondrous mercy, and so close at hand, too! "Tomorrow." Imminent danger brings outstanding mercy, and when the lion is about to leap upon his prey, then comes the lionslayer and breaks his teeth, and delivers his lamb even from between his jaws. Glory be to God for such promises as he gives to his people in times of trouble, even such promises as he gave here.