Ruth 4:5; Deuteronomy 25:5

Then Boaz said, The day you buy the field from the hand of Naomi, you also acquire Ruth1 the Moabite, the widow of the dead, in order bto perpetuate the name of the dead in his inheritance.


Laws Concerning Levirate Marriage

eIf brothers dwell together, and one of them dies and has no son, the wife of the dead man shall not be married outside the family to a stranger. Her fhusband's brother shall go in to her and take her as his wife and perform the duty of a husband's brother to her.