The sanction is based on I Corinthians 5, which directs Witnesses to "remove the wicked from among yourselves" and is necessary, said Witnesses national spokesman J.R. Brown, to preserve the religion's "moral integrity and cleanliness" in a corrupt world soon to be destroyed by God Jehovah.
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Jehovah's Witness elders -- all are men -- are the equivalent of ministers in other religions. Though unpaid, they take on responsibilities such as teaching Bible lessons and passing on denomination policy. They also investigate Witnesses accused of committing crimes against other Witnesses. In some of these cases, the police are never called.
Among the elders' primary tasks is serving on small judicial committees that hear confessions and decide whether an offense is worthy of excommunication.
Excommunications are announced to the congregation, but elders never say why a person was expelled. Witnesses can only guess from a long list of offenses that range from smoking cigarettes to manslaughter. Homosexuality, fornication, drunkenness, slander, fraud, gambling, apostasy, fits of anger and violence, and adultery are others.
The excommunication announcement tells members to begin shunning that person. If they don't, they, too, risk being disfellowshipped. Fear of being disfellowshipped is gripping for many Witnesses. Because they believe that only Witnesses will be saved from death, many don't associate with non-Witnesses.
Being disfellowshipped, then, means losing your circle of friends, not to mention family members who remain in the faith.
Elders disfellowship 50,000 to 60,000 Witnesses around the world each year, Brown said.
"It's not an unusual occurence, as far as we're concerned," he said.
http://www.sptimes.com/2002/08/22/Floridian/Spiritual_shunning.shtml