NEW YORK (JTA) — A Brooklyn man was sentenced to four years in federal prison for attempting to violently coerce a recalcitrant husband into giving a religious divorce.

Moshe Goldstein, 32, was sentenced Monday in federal court in Trenton, N.J., NJ.com reported. He pleaded guilty last year to committing extortion and to restraining, assaulting and injuring a man in 2011 on behalf of the man’s estranged wife.

Goldstein, his brother and seven other men, including two Orthodox rabbis, were arrested in October 2013 in an FBI sting operation. He is the first of the group — which is charged with running an operation that used threats of kidnapping, beatings and stun guns to pressure recalcitrant husbands — to be sentenced.

An Orthodox woman cannot obtain a divorce without receiving a “get” from her husband. Women who are trapped in marriages for this reason are called agunot, or “chained women.”

Rabbi Mendel Epstein was convicted of conspiracy to commit kidnapping and Rabbi Martin Wolmark pleaded guilty to conspiracy. Both will be sentenced in December, along with three other members of the group.