The Lords Supper IMO should open to all who love the Lord Jesus in sincerity and truth and have placed their faith in the Lord Jesus..
Now, who should determine who loves the Lord Jesus in sincerity and truth, the prospective participant, or the church to whom the Lord Jesus has entrusted this ordinance?
It is really a no-brainer IMO, since it is the Lord's Supper, no church has the right to prohibit anyone from partaking.
There are arguments for both positions. My church, the ELCA, practices open communion: no one is barred from coming to the Table, though it's generally expected that if you are present and worshiping that you are a baptized Christian. On the other hand, the LCMS practices closed communion; and their reasons for doing so aren't without merit: when we come to receive the Holy Eucharist we are receiving the very flesh and blood of Jesus Christ, this isn't just a churchly ritual, it is a Holy Sacrament in which Christ Himself is tangibly present. There should be a deep reverence for receiving
God Himself. Further, when we partake we are
confessing our common faith; that's what "confess" means, to "together-admitting", "together-speaking". If we are not, in fact, confessing and are not together sharing in common faith (in particular here, the true body and blood of our God and Savior) then partaking of the Sacrament together becomes a kind of act of theater and hypocrisy--we are in some sense lying to one another and to God.
I think arguments can be made for both practices; it depends on the angle one wants to look.
But at no point can we imagine that this isn't a serious topic, because
it is. It may not seem that way if someone doesn't believe that the bread and wine are Jesus Christ Himself truly and actually; but for those of us who believe that this is Christ Himself--not a sign, a symbol, or a token,
but actual Jesus--it can't be anything other than a serious topic.
-CryptoLutheran