2 Samuel 3:9

So do God to Abner, and more also
He wishes the worst of evils to himself, such as he cared not to name; but left them to be supposed what he meant as utter ruin and destruction of himself, soul and body:

except as the Lord hath sworn to David, even so I do to him;
meaning if he did not do that David, which God had sworn should be done, namely, what follows, the translation of the kingdom to him; by which it appears that Abner knew of the promise and oath of God respecting this matter; and therefore acted against his conscience, in setting up Ishbosheth on the throne; which he knew would not prosper, and that he was fighting against God; which shows what a hardened wicked creature he was, and how far ambition, and being thought to be of consequence, will carry a man.