1 Samuel 1:9-11

9And Hannah rose up after they had eaten in Shiloh, and after they had drunk; (now Eli the priest sat upon the seat by the door-post of the temple of Jehovah;)

10and she was in bitterness of soul, and prayed to Jehovah, and wept much.

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