1 Samuel 26:21 - Clarke's commentary and critical notes on the Bible

Then said Saul, I have sinned: return, my son David: for I will no more do thee harm, because my soul was precious in thine eyes this day: behold, I have played the fool, and have erred exceedingly. I have sinned - Perhaps the word חטאתי chatathi, "I have sinned," should be read, I have erred, or, have been mistaken. I have taken thee to be a very different man from what I find thee to be. Taken literally it was strictly true. He often purposed the spilling of David's blood; and thus, again and again, sinned against his life.