1 Samuel 15:23

For rebellion Disobedience to God's command; is as the sin of witchcraft Or the using divinations, and consulting familiar spirits, is as plainly condemned, and as certainly damnable and destructive. Stubbornness Contumacy, persisting in sin, justifying it, and pleading for it; is as iniquity and idolatry Or, rather, the iniquity of idolatry, the highest degree of wickedness. The meaning is, that as Saul had wilfully disobeyed the command of God, he was guilty of rebellion against him; and that wilful, peremptory disobedience to any command of God is, for the nature of it, a most heinous sin, though the matter in which it is manifested be ever so small. The Lord hath rejected thee from being king That is, hath pronounced the sentence of rejection; for that he was not now actually deposed by God, plainly appears in that not only the people, but even David, after this, owned him as king. Indeed, he continued to be king till the day of his death. He was only actually rejected and deposed when he was slain in battle. But the expression may chiefly respect his posterity, to whom God would not suffer the kingdom to descend.