Apocalypse 2:6

3. The Nicolaitanes are the followers of that Nicolas who was one of the seven first ordained to the diaconate by the apostles. They lead lives of unrestrained indulgence. The character of these men is very plainly pointed out in the Apocalypse of John, [when they are represented] as teaching that it is a matter of indifference to practise adultery, and to eat things sacrificed to idols. Wherefore the Word has also spoken of them thus: “But this thou hast, that thou hatest the deeds of the Nicolaitanes, which I also hate.”

A brother heretic emerged in Nicolaus. He was one of the seven deacons who were appointed in the Acts of the Apostles. He affirms that Darkness was seized with a concupiscence, and, indeed, a foul and obscene one, after Light: out of this permixture it is a shame to say what fetid and unclean (combinations arose). The rest (of his tenets), too, are obscene. For he tells of certain Æons, sons of turpitude, and of conjunctions of execrable and obscene embraces and permixtures, and certain yet baser outcomes of these. He teaches that there were born, moreover, dæmons, and gods, and spirits seven, and other things sufficiently sacrilegious. alike and foul, which we blush to recount, and at once pass them by. …

There are, however, among the Gnostics diversities of opinion; but we have decided that it would not be worth while to enumerate the silly doctrines of these (heretics), inasmuch as they are (too) numerous and devoid of reason, and full of blasphemy. Now, even those (of the heretics) who are of a more serious turn in regard of the Divinity, and have derived their systems of speculation from the Greeks, must stand convicted (of these charges). But Nicolaus has been a cause of the wide-spread combination of these wicked men. He, as one of the seven (that were chosen) for the diaconate, was appointed by the Apostles. (But Nicolaus) departed from correct doctrine, and was in the habit of inculcating indifferency of both life and food. …

6. “This thou hast also, that thou hatest the deeds of the Nicolaitanes.”] But because thou thyself hatest those who hold the doctrines of the Nicolaitanes, thou expectest praise. Moreover, to hate the works of the Nicolaitanes, which He Himself also hated, this tends to praise. But the works of the Nicolaitanes were in that time false and troublesome men, who, as ministers under the name of Nicolaus , had made for themselves a heresy, to the effect that what had been offered to idols might be exorcised and eaten, and that whoever should have committed fornication might receive peace on the eighth day. Therefore He extols those to whom He is writing; and to these men, being such and so great, He promised the tree of life , which is in the paradise of His God.

16. But it will be urged that the bad outside are worse than those within. It is indeed a weighty question, whether Nicolaus, being already severed from the Church, or Simon, who was still within it, was the worse, the one being a heretic, the other a sorcerer. But if the mere fact of division, as being the clearest token of violated charity, is held to be the worse evil, I grant that it is so. Yet many, though they have lost all feelings of charity, yet do not secede from considerations of worldly profit; and as they seek their own, not the things which are Jesus Christ’s, what they are unwilling to secede from is not the unity of Christ, but their own temporal advantage. Whence it is said in praise of charity, that she "seeketh not her own."

9. Not all bishops are bishops indeed. You consider Peter; mark Judas as well. You notice Stephen; look also on Nicolas, sentenced in the Apocalypse by the Lord’s own lips, whose shameful imaginations gave rise to the heresy of the Nicolaitans. “Let a man examine himself and so let him come.” For it is not ecclesiastical rank that makes a man a Christian. The centurion Cornelius was still a heathen when he was cleansed by the gift of the Holy Spirit. Daniel was but a child when he judged the elders. Amos was stripping mulberry bushes when, in a moment, he was made a prophet. David was only a shepherd when he was chosen to be king. And the least of His disciples was the one whom Jesus loved the most. My brother, sit down in the lower room, that when one less honorable comes you may be bidden to go up higher. …

4. Have mercy I beseech you upon your soul. Consider that God’s judgment will one day overtake you. Remember by what a bishop you were ordained. The holy man was mistaken in his choice; but this he might well be. For even God repented that he had anointed Saul to be king. Even among the twelve apostles Judas was found a traitor. And Nicolas of Antioch, a deacon like yourself, disseminated the Nicolaitan heresy and all manner of uncleanness. I do not now bring up to you the many virgins whom you are said to have seduced, or the noble matrons who have suffered death because violated by you, or the greedy profligacy with which you have hied through dens of sin. For grave and serious as such sins are in themselves, they are trivial indeed when compared with those which I have now to narrate. …