Make me worthy to partake without condemnation of Your most pure Mysteries, for the remission of my sins, and unto life everlasting. Amen. (Prayer before Holy Communion)
Philoxenus of Mabbug (d. 523) was a noted Syriac Christian bishop of the early 6th Century who sided with the Monophysites. Here he writes quite beautifully of the power of the Eucharist to forgive sins. He encourages Christians not to abstain from the Eucharist if they sin but rather to come to Christ in the Eucharist to be forgiven.
“…Recalling by these words what our Lord said to his disciples when he distributed his Mysteries to them:
This is my body which was broken for you for the forgiveness of sins, and this is my Blood which is shed for you for forgiveness (Mt. 26:26-8).
Thus it is that when we approach the Mysteries of our Saviour, we approach as needy sinners; for there is no need for medicine except in the case of an illness, or for healing except when someone is sick. For it is not the healthy who are in need of a doctor, but those who are ill. (Mt. 9:12) It is evident, then, that everyone who approaches the Mysteries receives them for the forgiveness of his sins, whether it be the priest or the people. And if the Holy Spirit is not within us because we are sinners, by what authority does the priest invoke the Spirit, or the people approach the Mysteries? There is the further point, that if the Holy Spirit is not within us, then neither is baptism effective in us – and how can we approach the Sacrament without being baptized? For it is clear that if the Holy Spirit leaves us whenever we sin, our baptism also departs from us, for our baptism is the Holy Spirit. When our Lord said to his disciples John baptized with water, but you shall be baptized with the Holy Spirit after not many days (Acts 1:5) , he was speaking of the Holy Spirit who came down upon the disciples in the upper room in the form of tongues of fire.
This descent of the Holy Spirit he calls ‘baptism’ because the apostles’ baptism then was by the Spirit alone, for they had already been baptized in water by John. It is the same now with us who are baptized: neither the wetness of the water in which we are baptized, nor the oiliness of the oil with which we are anointed, remain with us after death, but the Holy Spirit, who is mingled in our souls and bodies through the oil and the water, does remain with us, both in this life and after our death. For he is our true baptism, and for this reason we remain always baptized, for the Holy Spirit is within us always, and no sin can strip us of our baptism – neither adultery, nor theft, nor fornication, nor false testimony nor any action of this sort: only the denial of God and consorting with demons can do this, for in such cases the Holy Spirit really does depart, for he does not consent to remain in a place where Satan dwells. For what fellowship does Christ have with Satan or the believer with the unbeliever, or God’s temple with that of demons? (2 Cor. 6:14) [….]
How then should a sinner approach to receive the Holy Mysteries, if he does not have within himself the Holy Spirit who authorizes him to do this? For just as someone who has not been baptized is not permitted to come to the Mysteries, the same would apply to a sinner if it were true that the Holy Spirit had left him, which is the foolish opinion of those who say, ‘he is not allowed to approach the Mysteries’. If a sinner cannot approach the Mysteries, who then may do so? And what about the words ‘this is my Body which is broken for you for the forgiveness of sins’, and ‘this is my Blood which is shed for you for the forgiveness of sins?’ (Matt. 26:26-8)” ( The Syriac Fathers on Prayer and the Spiritual Life, pp 111-113, 124-125)