We must not think we have ever done anything which causes us arrogance, rather we must realize that if evil is committed by God, as King David said that when Shimie Ben Geirah was cursing him this was God’s words through him (though Shimie was liable to be punished because he chose to do evil, nonetheless, it was literally God speaking through him) thus how much infinitely more so, when we do good is it really only God (though of course we can be rewarded for choosing good.)