Irenaeus of Lyons · a new plain-English translation from the original language
In sending you, my dearest friend, this fourth book of the work concerning the detection and overthrow of the falsely called knowledge, we shall, as we promised, confirm through the sayings of the Lord the things we have already stated, so that you, just as you asked, may from every quarter receive from us occasions for refuting all the heretics, and, having thoroughly beaten them back, not allow them to go on further into the depths of error, nor be suffocated in the sea of ignorance, but rather, by turning them into the harbor of truth, may bring them to obtain their own salvation. Now the one who wishes to convert them must know carefully their rules, or their arguments. For it is not possible for anyone to treat those who are sick unless he knows the disease of those who are unwell. For this reason those who came before us, though far better men than we, were nevertheless not able sufficiently to refute the followers of Valentinus, because they did not know their rule, which we have handed on to you in the first book with all diligence, and in which we also showed their teaching to be a recapitulation of all the heresies. For this reason too, in the second book, we have held them up as it were a mirror of the whole overthrow. For those who refute them as they ought thereby refute all who hold wicked opinions; and those who overturn these overturn every heresy.
For their rule is blasphemous beyond all others, seeing that they say the Maker and Fashioner, who is the one God, as we have shown, was emitted out of a defect or falling-away. They blaspheme also against our Lord, cutting apart Jesus from Christ, and Christ from the Savior, and the Savior in turn from the Word — that Word which itself proceeds from the Only-begotten. And just as they say the Maker was emitted out of a defect or falling-away, they have likewise taught that Christ and the Holy Spirit sprang forth because of that same defect, and that the Savior is the fruit of those Aeons who were themselves emitted from the defect — so that nothing among them is without blasphemy. In the book, then, that comes before this one, the opinion of the apostles concerning all these things has been set forth, showing that those who from the beginning were eyewitnesses and servants of the word of truth held nothing of this kind, but instead urged us to flee opinions of this sort, foreseeing by the Spirit those who would lead the simpler people astray.
For just as the serpent deceived Eve, promising her what he did not himself possess, so too these men, putting forward a greater knowledge and unspeakable mysteries, and promising that reception into what they call the Pleroma, plunge into death those who believe them, turning them into renegades against their own Maker. And in that former case the apostate angel, working through the serpent the disobedience of man, thought to escape the notice of the Lord; for which reason God assigned to him the same form and name as the serpent. Now, however, since these are the last times, evil is being extended among men, not only turning them into renegades, but also, through many devices — that is, through all the heretics who have already been mentioned — establishing them as blasphemers of the Fashioner. For all these, although they come forth from different quarters and teach different things, nevertheless converge upon the same purpose of blasphemy, dealing a mortal wound through their slander of God our Maker and Nourisher, and through their contempt for man's salvation. Now man is a temperate blending of soul and flesh, shaped after God's likeness and formed by his two hands — namely the Son together with the Holy Spirit — to whom he also spoke, saying, 'Let us make man' — such, then, is the purpose of him who envies our life: to make men unbelieving of their own salvation, and blasphemers against God the Fashioner. For whatever grave things all the heretics may say, in the end they all arrive at this: that they blaspheme the Maker, and deny the salvation of God's handiwork, which is indeed the flesh — for the sake of which we have shown, in many ways, that the Son of God carried out the whole dispensation, and we have made it clear that Scripture calls no one else God save the Father of all, the Son, and those admitted into sonship.