Old Testament readings use the Septuagint , the Scripture the apostles quoted. Masoretic numbering shown for reference.Learn why
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2 Chronicles 20:15

and he said, “Listen, all Judah, and you inhabitants of Jerusalem, and you, King Jehoshaphat. Yahweh says to you, ‘Don’t be afraid, and don’t be dismayed because of this great multitude; for the battle is not yours, but God’s.

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