Irenaeus is considered by many the first systematic theologian of the Church. Being the first at something makes it is easy to ascribe to him the qualities of unerring thought and perfect insight.

Note: This article was written before the author’s conversion to Orthodoxy.

As much as my learning allows* I am undergoing a thorough reading of his books. In order to make them more easily understandable, I am annotating them like a study Bible.


*Some will say I do not have the scholarly background to undertake this task. All I can say is that they must judge my work on its own merits. I am grateful that God has provided for me in the past some decent instruction on Neo-Platonism when I studied the subject at Columbia University. My only peer-reviewed published work is on the Neo-Platonist doctrine of the Chain of Being. Understanding Neo-Platonism to some extent greatly assists me in knowing what the Gnostics were talking about.

Gnosticism is essentially the melding of Greek Dualist thought with the trappings of Christianity. It mixes Pythagoreanism, Platonism, and Greek Polytheism. There is nothing distinctly Christian about it.

Click here in order to read Book I of Irenaeus’ Against Heresies, with my annotations.

A few things I would like to reflect upon that are of interested, from a Reformed Theological apologetic standpoint:

  • There are many parts, which upon reflection, it appears that Irenaeus was writing extemporaneously. He misquotes parts of the Bible (particularly in Chapters 3 and 18.) For example, he says the Gospel of John records something that is only found in Matthew and Luke. Oftentimes, the Gnostic systems he records are internally inconsistent. A careful reader may notice it might not be that particular system, but rather Irenaeus is forgetting which branch of Gnosticism taught what, and this confusion finds its way into the text. Hence, my sense is that this book was not carefully edited nor was Irenaeus copiously recording from information out of books open right in front of him.
    • What are the ramifications of this for us? For one, it gives us reason to exercise caution when quoting Irenaeus as a be-all, end-all authority. The work gives us a sense of what orthodox Christians believed, but it does not reflect the most careful, studied thought. Further, when people cite that Irenaeus “as a child learned from Polycarp , who learned from John,” they often do so under the pretense that Irenaeus carefully re-presents John’s thought. Being that Irenaeus misremembers what the Gospel of John really says, which he surely owned a copy of, it is not wise to take seriously that he would remember tons of things that Polycarp would have taught him in immense detail.
  • To my surprise, Book I on several points teaches against Baptismal Regeneration (see chapter 21). Instead, it teaches a baptism of repentance, in line with the plain meaning of 1 Peter 3:21 and the writings of Justin Martyr and Origen (roughly Irenaeus’ contemporaries). I will reserve further comment on the subject until I read the entire corpus of Irenaeus’ works–but so far the evidence is suggestive that Justin and Origen do represent an earlier line of thought than later third century conceptions of the efficacy of the baptismal sacrament.