1 Samuel 1:3, 11

This man went up from his city each year to worship and sacrifice to the LORD of hosts at Shiloh. Hophni and Phinehas, the two sons of Eli, were priests to the LORD there.

She made a vow, saying, “O LORD of hosts, if You will indeed look on the affliction (suffering) of Your maidservant and remember, and not forget Your maidservant, but will give Your maidservant a son, then I will give him to the LORD all the days of his life; a razor shall never touch his head.”