John Gill Bible Commentary

Otherwise I should have wrought falsehood against mine own life,.... Or "soul"; he should not only have exposed his life to danger, but acted falsely to the king, by going contrary to his orders; yea, would have done that which was contrary to his own conscience; and if he had buoyed himself up with the hope of impunity, or of a reward, he should have found himself mistaken; the textual reading is, "against his life" (l), or "soul", the life of Absalom, by taking it away: for there is no matter hid from the king; this, though done ever so secretly, would have come to his knowledge by some means or another, and then I should have incurred his displeasure, and suffered for it: and thou thyself wouldest have set thyself against me; to accuse and bring him to justice; he would have been so far from protecting him, that he would have been the first man that would have insisted on it that he should be punished for it; or why dost not thou thyself set thyself against him, and smite him? thou mayest if thou pleasest, yonder he hangs, go and smite him. (l) , Sept. "contra animam illius", Piscator.