Mark 12:19
Master, Moses wrote unto us, If a man’s brother die, and leave his wife behind him, and leave no children, that his brother should take his wife, and raise up seed unto his brother.
Cross-reference
In Genesis 38:8, Judah applies the levirate marriage law, providing an OT example of the practice Jesus cites.
In Deuteronomy 25:5, the levirate marriage law is given; Jesus directly quotes this in Mark 12:19.
In Ruth 4:5, Boaz applies this Levirate law to redeem Naomi's family line, showing the law in practice.
Leviticus 18:16 forbids relations with a brother's wife while alive, setting the boundary for this Levirate allowance.
Matthew 22:24 records the same Sadducean quote of Moses' Levirate law, a direct parallel account.
Matthew 22:25 continues the same Sadducean hypothetical with the first brother.
Luke 20:33 poses the resurrection question based on this same Levirate scenario.
In Ruth 1:11-13, Naomi references this law to explain why she cannot provide husbands for her daughters-in-law.