When it comes to all these religions, shunning is a form of church discipline. Shunning should be applied to those who violate Church rules and do not repent. But not applied to an unbelieving individual. There's a difference. First of all, an unrepented Christian is sinning and not repenting of that action, which will cause others to stumble in their faith. What we see next is that an individual who is serving and still unrepented will allow that sin to show and will make it out as if it's all right to sin and not ask for forgiveness. A Church is supposed to be a place for the broken to become whole again. Not the broken remains broken and soon spread that brokenness. Although shunning is related to ex-communication, the two practices are not the same. To be excommunicated is to lose one’s membership rights in a church; the excommunicated person may no longer vote in the church, teach a class, etc. The Bible teaches 'ex-communication' as a form of church discipline NOT shunning. Here's the difference, 1 Corinthians 5:11 reads this, "But now I am writing to you not to associate with anyone who bears the name of brother if he is guilty of sexual immorality or greed, or is an idolater, reviler, drunkard, or swindler—not even to eat with such a one." When we read verses 2-11 we can understand the full context. Because the man was involved in "sexual immorality, or greed. Idolatry, etc." He loses his right to teach or serve in the church for 'his own spiritual good' Vs.2,  'the church’s purity' Vs.6. And the reason to "not eat with such a one" is mainly for this reason, the man claims to be a Christian, or he is consistently involved in public, unrepentant sin.