(John Chrysostom [347/347 - 407 A.D.] was the son of a rich family who studied law and then Scripture. An ascetic after baptism, he served as a priest in Antioch for 12 years. He was made Patriarch of Constantinople in 398. He was named "Golden Mouth" because he was an accomplished speaker. Although not totally orthodox on the teachings of the Lord's Supper, he does reflect the common practice of the church of his day.)
And how, you may ask me, can I know about this person or that person? I am not speaking of those you do not know, but of those you to know. And shall I say something more serious? It is not as dreadful to be possessed by evil spirits such as those of whom Paul speaks as to tread Christ under foot, and to hold the blood of the testament unclean, and offer an affront to the Spirit of grace (Heb. x. 29). He who has sinned, and comes to Holy Communion, is lower than one possessed by a demon. For those who are afflicted by an evil spirit are not on that account punished. But these others should they come, unworthy, to the altar, they are handed over to everlasting punishment.
Let us drive away not these only but all without exception whom we see draw near who are unworthy. Let no Judas receive, lest he suffer as Judas did. This Gathering is also the Body of Christ. Watch therefore, you who fulfil the office of deacon in these Sacred Mysteries, that you do not provoke the anger of the Lord by not purifying His Body: that you do not give a sword in place of food. And though such a one should approach the altar out of ignorance, exclude him, and be unafraid. Be in fear of God, not of man. For if you fear a man, you will be laughed at, even by him. But if you fear God, you will have the respect of men. Yet, if you do not dare to do this, then bring them to me. I shall not suffer that this be even attempted. I would lay down my life first, before I would present the Lord's Blood to one who was unworthy of It; and pour out my own blood rather than give this Fearful Blood contrary to what is fitting.
But if you do not know who is unworthy, though exercising much care, then there is no fault on your part. For what I am saying is about those who are well known. If we correct those, God will soon disclose those we do not know. But if we do not disturb those who are known to be unworthy, why should God make the others known to us? I say these things to you, not to drive these away, not simply to cut them off, but that we may lead them to do what is right, that we may take care of them. For by doing this God will be gracious to us, and we shall find many who will then receive worthily. And for our own zeal, and because of our care for the souls of others, our reward shall be very great. And to this may we all attain, by the grace and mercy of our Lord Jesus Christ, to Whom be honour and glory for ever and ever. Amen."
(P.G. 58, Hom. 82-3,par. 4, On Matthew, col. 743).