C. F. Keil and Franz Delitzsch on 2 Samuel 16:4

2Sa 16:4

And in the excited state in which David then was, he was weak enough to give credence to Ziba’s words, and to commit the injustice of promising the calumniator all that belonged to Mephibosheth, - a promise for which he most politely thanked him. השׁתּחויתי, “I bow myself,” equivalent to, I lay myself at thy feet. “May I find favour in the eyes of my lord the king!” i.e., may the king grant me his favour (vid., 1Sa 1:18).