1 Samuel 1:9-11

9 So Hannah rose up after they had eaten in Shiloh, and after they had drunk. Now Eli the priest sat on a seat by a post of the temple of the LORD.

10 And she was in bitterness of soul, and prayed to the LORD, and wept sore.

11 And she vowed a vow, and said, O LORD of hosts, if you will indeed look on the affliction of your handmaid, and remember me, and not forget your handmaid, but will give to your handmaid a man child, then I will give him to the LORD all the days of his life, and there shall no razor come on his head.