1 Chronicles 19:10-12

10Now when Joab saw that the battle was set against him before and behind, he chose from all the best of Israel, and put them in array against the Syrians.12 11And the rest of the people he delivered to the hand of Abishai his brother, and they set themselves in array against the children of Ammon.3 12And he said, If the Syrians shall be too strong for me, then thou shalt help me: but if the children of Ammon shall be too strong for thee, then I will help thee.