Genesis

If brethren dwell together, and one of them die, and have no child, the wife of the dead shall not marry without unto a stranger: her husband’s brother shall go in unto her, and take her to him to wife, and perform the duty of an husband’s brother unto her.

Then said Boaz, What day thou buyest the field of the hand of Naomi, thou must buy it also of Ruth the Moabitess, the wife of the dead, to raise up the name of the dead upon his inheritance.

And his name shall be called in Israel, The house of him that hath his shoe loosed.