The practice of Communion or the Lord's Supper was instituted by Jesus himself just before he was arrested and crucified. The unleavened bread is taken to signify Christ's body, "which is given for you" (Luke 22:19), and the wine to signify Christ's blood, which "is poured out for you" (Luke 22:20). The ceremonial aspects of this sacrament vary throughout Christendom, but beliefs about privately partaking and partaking without an ordained minister or priest are especially contested.
Is it okay for Christians to celebrate Communion outside of church?
However, at the time of the New Testament's authorship, "the church" consisted of small groups of Christians in homes. There were appointed leaders (Titus 1:5), but they were not specifically called to preside over the Lord's Supper. Often a single church met exclusively in one house (Colossians 4:15), but they did not have the need, money, or means to have one building dedicated only as a meeting place or place of worship. In 1 Corinthians 11:25, Paul simply relates Jesus as saying "Do this, as often as you drink it, in remembrance of me." So, there does not appear to be a reason in the Bible itself that a private gathering of Christians could not observe Communion.
However, that being said, there are reasons various churches prohibit the private celebration of Communion which, while not found in the Bible itself, are worthy of consideration. First of all, any church which holds to consubstantiation, such as the Lutheran or Episcopal churches, are likely to hold the physical elements in much higher regard because of their theological beliefs about Communion. Other churches may become very concerned about Paul's reprimand of the church in Corinth and their taking of Communion "in an unworthy manner," which he said was why "many of you are weak and ill, and some have died" (1 Corinthians 11:27, 30). While these warnings are about attitudes and beliefs, not places or forms, some feel that there is less danger of the Lord's Supper being abused similarly to how it was in Corinth if Communion is only done under the auspices of the church itself.
Communion is a very important, beautiful sacrament in which Christians are commanded to partake. As such, appropriate reverence, respect, and ceremony should be observed. It is a matter of conscience whether this can be accomplished without a minister or outside a church setting, but the Bible certainly does not prohibit it.
What is the significance of the Lord's Supper?
What is the biblical frequency of Communion?
Is Communion supposed to be open or closed?
Is the celebration of a first Communion / Eucharist biblical?
What is the reason for all the different Christian interpretations?
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