Deuteronomy 25:9

then shall his brother's wife come unto him in the presence of the elders, go directly up to him right there in public, because he was bound to submit to what followed, and loose his shoe from off his foot, and spit in his face, and shall answer and say, So shall it be done unto that man that will not build up his brother's house. Her act of contempt in a way compensated her for the reproach which the man heaped upon her by refusing to marry her, and thus to found and establish his brother's family. The taking off of the shoe was a custom signifying the ceding of a piece of ground or property to some one else, just as one declares his rights of ownership by stepping upon such property. The disgrace in this case consisted in the fact that the woman loosed the man's shoe, thus publicly depriving him of his right to the property of his dead brother.