Deuteronomy 21:12

The shaving the head (a customary sign of purification, Leviticus 14:8; Numbers 8:7), and the putting away “the garment of her captivity,” were designed to signify the translation of the woman from the state of a pagan and a slave to that of a wife among the covenant-people. Consistency required that she should “pare” (dress, compare 2 Samuel 19:24), not “suffer to grow,” her nails; and thus, so far as possible, lay aside everything belonging to her condition as an alien.