Deuteronomy 25:9

“Then shall his brother’s wife come unto him in the presence of the elders, etc.] The time and place being appointed the evening before by three Rabbins, and two witnesses, as Leo of Modena says f457; of which she was apprized, and ordered to come tasting: and loose his shoe from off his foot; his right foot, which was thus done; “they bring him a leather shoe, which has a heel, but not sewed with linen (linen thread), and he puts it on the right foot, and binds the latchet on his foot, and stands, he and she, in the court; he fixes his foot on the ground, and she sits and stretches out her hand in the court, and looses the latchet of his shoe from off his foot, and pulls off his shoe, and…”

“The law of levirate marriage. The law on this subject is not unique to the Jews, but is found (see Genesis 38:8) in all essential respects the same among various Oriental nations, ancient and modern. The rules in these verses, like those upon divorce, do but incorporate existing immemorial usages, and introduce various wise and politic limitations and mitigations of them. The root of the obligation here imposed upon the brother of the deceased husband lies in the primitive idea of childlessness being a great calamity (compare Genesis 16:4; and note), and extinction of name and family one of the greatest that could happen (compare Deuteronomy 9:14; Psalms 109:12-15). To avert this the…”

“Loose his shoe - As a sign of his resignation of all his right to the woman, and to her husband's inheritance: for as the shoe was a sign of one's power and right, Psa 60:8, Psa 108:9, so the parting with the shoe was a token of the alienation of such right; and as a note of infamy, to signify that by this disingenuous action he was unworthy to be amongst free - men, and fit to be reduced to the condition of the meanest servants, who used to go barefoot, Isa 20:2, Isa 20:4. Deuteronomy 25:10”

“25:9 pull his sandal from his foot: Using footwear, which touched the ground, the brother-in-law showed that he relinquished any claim to his dead brother’s estate (Ruth 4:7). • spit in his face: This is an almost universal gesture of utter contempt (see Num 12:14).”

“loose his shoe: Pulling off the shoe seems to express his being degraded to the situation of slaves, who generally went barefoot; and spitting in or rather before (biphney) his face, was a mark of the utmost ignominy. Rut 4:7, Rut 4:8; Isa 20:2; Mar 1:7; Joh 1:27 spit: Num 12:14; Job 30:10; Isa 50:6; Mat 26:67, Mat 27:30; Mar 10:34 So shall: Gen 38:8-10; Rut 4:10, Rut 4:11; Sa1 2:30 Deuteronomy 25:11”