Elkanah her husband said to her, Do what seems you good; wait until you have weaned him; only Yahweh establish his word. So the woman waited and nursed her son, until she weaned him.
The Mosaic Law required an offering to God when He granted a vow (Leviticus 27:1-8). Elkanah went to the central sanctuary to make this offering shortly after Samuel’s birth (1 Samuel 1:21). The text refers to Hannah’s vow as Elkanah’s (1 Samuel 1:21). It was his vow in this sense: since he did not cancel it when he heard about it, he became responsible for it as Hannah’s husband (cf. Numbers 30:1-8).