2 Samuel 15:30-31

30But David continued up the Mount of Olives, weeping as he went; his head was covered and he was barefoot. All the people with him covered their heads too and were weeping as they went up.

31Now David had been told, “Ahithophel is among the conspirators with Absalom.” So David prayed, “ LORD, turn Ahithophel’s counsel into foolishness.”