Luke

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.

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

Saying, Master, Moses said, If a man die, having no children, his brother shall marry his wife, and raise up seed unto his brother.

And Judah said unto Onan, Go in unto thy brother’s wife, and marry her, and raise up seed to thy brother.

And Moses wrote this law, and delivered it unto the priests the sons of Levi, which bare the ark of the covenant of the Lord, and unto all the elders of Israel.