The issue of the Lord’s Supper can be a very emotional one, especially as it involves the question of who can and who cannot attend at any particular altar. For those who prefer the emotional route to theology, there is nothing here that will settle your mind and heart. I would simply ask that you approach this post with the desire to learn the “why” of the “close communion”.
I want to look at this briefly from three points from the Holy Scriptures.
First, when our Lord Christ says to His disciples, “Take eat, this is my body… Take drink, this is my blood” He is not doing so metaphorically, symbolically, or allegorically. He is speaking on the basis of the entire Old Testament that eating and drinking the sacrifices for sin and the establishment of covenant with God are necessary to gain the benefits of that sacrifice. Being the final sacrifice as the true Lamb of God (not metaphorically, symbolically, or allegorically a sacrifice), the benefits of what the sacrifice accomplishes comes to us through the eating and drinking of the flesh of sacrifice. (I don’t make this stuff up! Go search the Scriptures!)
Second, St. Paul, knowing this truth that the body and blood of Jesus are present and distributed to those gathered to receive, reminds us all in 1 Corinthians 11:27-29 that to receive the elements of the Supper without recognition of the body and blood of Christ is guilty of sinning and brings harsh judgment on themselves. The pastor of a congregation is charged by the Lord to be stewards of the mysteries of Christ (and this would qualify as a mystery, I would think), As a result of this charge they are held accountable for the souls under their care as we see in Hebrews 13:17. A pastor knows his flock and so can vouch for them with confidence. A stranger he does not know, so for the protection of all, close communion.
Third, and related to the above, there is the obvious fact that there is division in the earthly church, and most all of the divisions relate back to Jesus and the cross. True unity of the church is possible in this world only through true unity of teaching. For example, how can one group say that Jesus was born of a clinical virgin, was fully God and fully man in one Christ, died as the Lamb of God on the cross to take away all sins, and physically rose from the dead after three days also claim to be in untiy of teaching with those groups who deny all of it? Two different teachings, two different Christs! As the communion is a demonstration of the oneness of faith and the avoidance of error (Acts 2:42; 1 Corinthians 10:17; 1 Corinthians 11:26; Romans 16:17) we are bound to make the confession and practice close communion for the very sake of the Gospel.
How dare we practice a close communion? A better question is: how dare we not?