And say — That is, as faithful to thee, as I have been to thy father. David's suggesting this crafty counsel must be reckoned amongst his sins. Nevertheless God was pleased to direct this evil advice to a good end.
Related Commentaries of 2 Samuel 15:34
2 Samuel 15:34
34 But if thou return to the city, and say unto Absalom, I will be thy servant, O king; as I have been thy father's servant hitherto, so will I now also be thy servant: then mayest thou for me defeat the counsel of Ahithophel.