St. Paul taught that we must discern the Body and the Blood of the Lord to receive the Eucharist. We must be prepared by faith, understanding and an examination of our conscience. This is the most holy moment for any Christian and we must be sure of our preparation as every aspect of our demeanor must be prepared to reflect the respect, solemnity and joy that are received at the reception of our Lord and Saviors real body and blood. This is the most extraordinary moment that anyone can experience on this earth. We are to be reminded of the words of the Centurion, “Lord, I am not worthy that you should enter my roof, but only say the word and my soul will be healed.”
Is it possible to have open communion with those who do not share in our belief in the real corporeal presence of Christ in the Eucharist? Could we, in fact be harming those who we allow at the Lord's Table who do not discern the Lord's Body and Blood? Would we be contributing to them bringing condemnation on themselves by sharing the Eucharist with them? Certainly, I cannot receive or participate in Protestant communion where it is only symbolic as it makes a mockery of the Sacrament established by Christ. Under what circumstance do I believe that communion is possible in good conscience? When we share the same respect and reverence in knowing, that it is the Body and Blood of the living Christ that we adore and worship before we receive, then we can share communion. What do I mean by respect and reverence?
We must be in a state of grace, one conscience of grave sin must not receive communion before the Sacrament of Reconciliation. As part of the preparation we must also fast prior to the receiving of the Eucharist. There must also be a union of doctrine and authority as the Sacrament is one of oneness with Christ and His Church, St. Paul taught that we are to be one Body and partake of one bread. This oneness includes the members of the Orthodox communities and certain Catholic communities not in full communion of authority but in agreement on doctrine. The Catholic and the Orthodox Church are to be seen as the two ”lungs” of the one Church of Christ.
Unfortunately, it is impossible for communion with those ecclesiastical communities coming out of the Reformation because they lack a valid priesthood and a means to confect the Eucharist as well as the proper understanding of the sacrament.