The Corinthian warnings
There are hardly any more serious warnings addressed to Christians in the New Testament than the warnings that surround communion in Paul's first letter to the Corinthians. Paul says in chapters 10 and 11 that the wrong taking of the bread and wine stirs up God's jealousy and can lead to weakness, illness and even God's final discipline - death ("falling asleep").
Some Christians have read these with fear and trepidation and even avoided communion because of them - or shall we say possibly because of a misunderstanding of them.
We guard what is precious
What is precious we surround with a hedge of protection. The more precious, the more protection we build in. This is what Paul is doing. He is guarding the table with warnings because it is so precious. That's how to understand the severe nature of the warnings - they point to the precious nature of the ordinance.
What is so precious about Communion?
Two features of this ordinance are precious. First, in some wonderful way we are communing with Jesus Christ, "participating in his blood and body" (10:16). We are going beyond obedience, "do this in remembrance of me", we are going beyond revealing our trust in the atoning sacrifice of Jesus Christ which the elements speak of, we are in some mysterious - and even mystical - way communing with our Saviour. Communion, perhaps, is as close fellowship as we get in this world with Jesus - there shall be no cup in heaven, for then we shall see him face to face.
Secondly, tearing a piece off the one loaf of bread is a symbol of our one-ness in Christ (10:17). We each take a piece which came from one loaf - we are each one part of the one body of Christ. And so, again, in a wonderful way, we are being reminded that we are all one in Christ, one Lord, one faith, one Spirit, one baptism.
See why the warnings?
So now we can see why all the strong warnings! Fellowship with Jesus is precious! The one body of Christ for whom he has died - the unity of it - is precious! How can we partake of cup of the Lord and the cup of demons? How can we take communion on one day of the week, but commit spiritual adultery another day by loving and offering ourselves to another? That will rouse God's jealousy (10:22). How can we take of the one loaf, but then go on to neglect the body of Christ or harm it in any way? These are dangerous contradictions, lethal hypocrisies.
And hence we are called to examine ourselves before we eat and drink.
Do we love Jesus Christ more than any other?
Are there rival idols in our hearts or lives?
Do we love our brothers and sisters?
Do we freely forgive them for offenses?
Do we do nothing to harm the body?
The purpose of these warnings is not to scare us as we eat, but to wake us up before we eat, and to encourage us to repent of our sins and by his grace get ourselves right with God and our fellow man.
So that instead of being a dangerous sacrament, communion becomes the precious blessed one it is meant to be.