Although called different things in different denominations, there is a process of separating congregants from the body of their house of prayer. Most religions also offer offending members a way back into the fold. Some clergy whose denominations practice the concept explain how it works.
Excommunication means being placed outside the community. At one time, people who were divorced were automatically excommunicated, but that was rescinded decades ago. Certain offenses are designated as serious and separate someone from the community. There are many misunderstandings about excommunication, even among Catholics. God is not turning his back on you. You're turning your back on God and doing things that are damaging to the Church community.
As a community, the Church has shaped itself in certain ways and attempts to maintain its values. So, if your behavior hurts the community or is contrary to those values, that may be a reason to consider excommunicating someone. An excommunicated person cannot take part in Communion and other sacraments and activities.
An excommunicated person can attend services. Over time, we hope that an excommunicated person will return to the Church in good standing. After all, if only perfect people attended church, we'd have small congregations.
The important thing is that excommunication is not permanent. One can repent. The goal is for the person to return to the Church in good standing.
There are three purposes for excommunication: to maintain the integrity of the church, to encourage people to change or to protect potential victims.
As a member of The Church of Latter-day Saints, you agree to live your life within certain boundaries and by certain teachings of the church. If you don't do that, then you could face excommunication.
You also could be excommunicated if your behavior is seriously inappropriate. Say you're committing crimes of moral turpitude: robbery, burglary, assault, etc.
There also are instances of excommunication when someone joins the church to have access to people he or she would victimize.
While I have not participated in an excommunication in my current position, I have in previous positions. When I was a stake, which meant I was over multiple churches, I and other stakes would come together for the excommunication of a member.
What you have to understand is that we're excommunicating, or separating, the person from the body of the church. The person isn't being excommunicated from God. No one can do that.
We don't want anyone to be excommunicated. We want you in the church. We just can't have you in the church if your presence is a detriment to the other members of the church. Even if you are excommunicated, you still can attend church. You just don't have full access to the church. You can't take part in Communion. You can't vote, and there are other things you can't do.
Excommunication is not permanent. We would council with you in the hope of helping you return to the church in good standing.
The Rev. K.P. Titus, New York Bible Assembly of God, Floral Park:
We don't call it excommunicate, but we do have a process when a person misbehaves and needs to be separated from the body of the church.
If it were a member of the clergy, we'd ask him to step down from leading a church. For example, if a clergy were to divorce and then remarry, that person can't continue to be a minister. He can still be a member but not a minister.
The person can continue attending church, but we'd ask them not to take Communion, hold office in the church or vote.
Anyone, even someone who is excommunicated, can come to the church. The church is open to everyone. And, I have to stress that we're not divorcing the person from God, only from the church or from some church privileges: Holy Communion, the time of testimony by believers, being a board member or a voting member.
We only do this in very serious cases. It is conducted by the church board. The main thing is that we want to work with the person to get him or her back in the church and back in good standing.