Deuteronomy 25:5 - 25:10
5 “If brothers live together and one of them dies and has no son, then the wife of the one who died shall not be married outside the family to a strange man. Her husband’s brother shall go in to her and take her to himself as wife and perform the duty of a husband’s brother to her. 6 And it will be that the firstborn whom she bears shall assume the name of his dead brother, so that his name will not be blotted out from Israel. 7 But if the man does not desire to take his brother’s wife, then his brother’s wife shall go up to the gate to the elders and say, ‘My husband’s brother refuses to raise up a name for his brother in Israel; he is not willing to perform the duty of a husband’s brother to me.’ 8 Then the elders of his city shall summon him and speak to him. And if he stands and says, ‘I do not desire to take her,’ 9 then his brother’s wife shall come to him in the sight of the elders and pull his sandal off his foot and spit in his face; and she shall answer and say, ‘Thus it is done to the man who does not build up his brother’s house.’ 10 And in Israel his name shall be called, ‘The house of him whose sandal is removed.’