1 Samuel 24:22

David sware unto Saul. Quest. How then could David destroy so many of Saul's sons, 2 Samuel 21:8,9 ? Answ. David could bind himself by his oaths, but he could not bind God, to whose good pleasure all promises, vows, and oaths must in all reason be submitted; and that was done by God's command, and God was well pleased with it, 2 Samuel 21:14. Nor is it to be supposed that David sware not to destroy any of them in case God should specially command it, or that should by miscarriage render themselves obnoxious to the sword of justice; but only that he would not do it barely on his own private account, nor seek occasions of so doing. Unto the hold, to wit, of En-gedi, 1 Samuel 24:1; for having had so great and frequent experience of Saul's inconstancy, and malice, and perfidiousness, he would trust him no more.