12:21

the second married her: Among the ancient Hebrews, if a man died sonless, it was expected that his brother would marry the widow in order to produce offspring to continue the dead man’s family line. (Ge 38:8) The arrangement, later incorporated into the Mosaic Law, was known as brother-in-law, or levirate, marriage. (De 25:5, 6) Brother-in-law marriage was practiced in Jesus’ day, as shown by the Sadducees’ reference to it here. The Law did permit relatives to refuse to perform brother-in-law marriage, but if a man would not “build up his brother’s household,” he brought disgrace on himself.​—De 25:7-10; Ru 4:7, 8.