Deuteronomy 25:8-10

8Then 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,’ 91then his brother’s wife shall come to him in the sight of the elders, and pull his sandal off his foot and 2spit in his face; and she shall 3declare, ‘Thus it is done to the man who does not build up his brother’s house.’ 10In Israel his name shall be called, ‘The house of him whose sandal is removed.’