2 Samuel 18:5-7

And the king ordered Joab and Abishai and Ittai, “Deal gently for my sake with the young man Absalom.” And all the people heard when the king gave orders to all the commanders about Absalom. So the army went out into the field against Israel, and the battle was fought in the forest of Ephraim. And the men of Israel were defeated there by the servants of David, and the loss there was great on that day, twenty thousand men.