But Saul and the people spared Agag, and the best of the sheep, and of the oxen, and of the fatlings, and the lambs, and all that was good, and wouldn't utterly destroy them: but everything that was vile and refuse, that they destroyed utterly.
Now he has shown a pattern of disobedience up to this point. He has become self-willed, doing his own thing. So the prophet is coming and warning him. This to me is very significant, because God does seek to warn us from our self-willed path of destruction. God doesn't just let you trip off into the path of destruction, without coming and giving you fair warning, oftentimes, repeated warnings.