'Vow' in the Bible

Making a vow, she pleaded, “Lord of Hosts, if You will take notice of Your servant’s affliction, remember and not forget me, and give Your servant a son, I will give him to the Lord all the days of his life, and his hair will never be cut.”

When Elkanah and all his household went up to make the annual sacrifice and his vow offering to the Lord,

“As for me, I vow that I will not sin against the Lord by ceasing to pray for you. I will teach you the good and right way.