2 Samuel 14:11
Then said she, I pray thee, let the king remember the LORD thy God, that thou wouldest not suffer the revengers of blood to destroy any more, lest they destroy my son. And he said, As the LORD liveth, there shall not one hair of thy son fall to the earth.
The verse stands inside Joab's efforts to secure reconciliation between Absalom and David. In it the king gives the woman assurance that her surviving son will be protected from the revengers of blood. He binds that protection with an oath by the living LORD that not one hair of the young man shall fall to the ground, meaning he will come to no harm whatever. The reconciliation gained through this episode was afterward betrayed when Absalom led a rebellion against his father.