For Pekah son of Remaliah
 Who was at this time king of Israel: 
 slew in Judah an hundred and twenty thousand in one day,
 which were all 
 valiant men;
 a great slaughter to be made at one time, and of valiant men, but not so great as that in ( 2 Chronicles 13:17 ) , 
 because they had forsaken the Lord God of their fathers;
 this was not a reason with Pekah for slaying them, he himself being an idolater, but why the Lord suffered them to be slain by him.