Deuteronomy 25:7-10

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 establish a name for his brother in Israel; he is not willing to perform the duty of a husband’s brother to me.’ Then the elders of his city shall summon him and speak to him. And if he persists and says, ‘I do not desire to take her,’ 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 declare, ‘Thus it is done to the man who does not build up his brother’s house.’ In Israel his name shall be called, ‘The house of him whose sandal is removed.’