Athenagoras was an Athenian philosopher converted to Christianity. He wrote around 170AD. We do not know much about him, but he is the earliest Christian opponent of remarriage (before Tertullian and Hippolytus) and invented the moral argument for God’s existence (and the physical resurrection for that matter.)
Are you missing anything else of possible importance? The following are just some notes I have taken from things that stuck out to me reading this early Christian witness:
A Plea for the Christians
It is written during the time of Marcus Aurelius and Commodus according to the preface, which gives the writing a date between 177 to 180 AD.
Chapter one says that Christians refuse to go to court against those who rob them and that they turn the other cheek.
Chapter two emphasizes that a Christian is known by his good works (i.e. “no Christian is a bad man unless he falsely profess our doctrines.”)
Chapter 7 says the Holy Spirit moved the mouth so the prophets like musical instruments.
[We have for witnesses of the things we apprehend and believe, prophets,men who have pronounced concerning God and the things of God, guided by the Spirit of God. And you too will admit, excelling all others as you do in intelligence and in piety towards the true God (τὸ ὄντως θεῖον), that it would be irrational for us to cease to believe in the Spirit from God, who moved the mouths of the prophets like musical instruments, and to give heed to mere human opinions.
The importance of this claim to us is that it shows that he believes that God manipulated the writers of Scripture in such a way that everything they penned was precisely the way God intended for it to come out. It is a valuable illustration of how the Scripture is “God-breathed” (2 Tim 3:16).
Chapter 9 continues on the preceding topic and pretty much says that the prophets were in a state of automatic writing:
I think that you also, with your great zeal for knowledge, and your great attainments in learning, cannot be ignorant of the writings either of Moses or of Isaiah and Jeremiah, and the other prophets, who, lifted in ecstasy above the natural operations of their minds by the impulses of the Divine Spirit, uttered the things with which they were inspired, the Spirit making use of them as a flute-player breathes into a flute.
Chapter 10 teaches the doctrine of the eternal generation of the Son.
[I]t occurs to you to inquire what is meant by the Son, I will state briefly that He is the first product of the Father, not as having been brought into existence (for from the beginning, God, who is the eternal mind [νοῦς], had the Logos in Himself, being frometernity instinct with Logos [λογικός]); but inasmuch as He came forth to be the idea and energizing power of all material things, which lay like a nature without attributes, and an inactive earth, the grosser particles being mixed up with the lighter.
Binitarians claim that Athenagoras did not affirm the deity of the Holy Spirit. While the way he talks of the Spirit maintains the Scriptural under-emphasis of the Spirit (He is not mentioned nearly with the frequency of the Father and the Son) the following teaches that Athenagoras affirms the Personhood and distinct nature of the Spirit:
The Holy Spirit Himself also, which operates in the prophets, we assert to be an effluence of God, flowing from Him, and returning back again like a beam of the sun. Who, then, would not be astonished to hear men who speak of God the Father, and of God the Son, and of the Holy Spirit, and who declare both their power in union and their distinction in order, called atheists?
Chapter 12 resumes the same topic:
[T]hey know God and His Logos, what is the oneness of the Son with the Father, what thecommunion of the Father with the Son, what is the Spirit, what is the unity of these three, the Spirit, the Son, the Father, and their distinction in unity.
Chapter 13 essentially says that Christians now offer God the bloodless sacrifice of faith. The significance of this is that the term “bloodless sacrifice” did not originally refer to the Eucharist and, as all acknowledge, the supposed propitiatory effect of partaking in the Eucharist was not something mentioned by most of the church fathers. The Antiochene Liturgies are an exemption to this.
[T]he Framer and Father of this universe does not need blood, nor the odour of burnt-offerings, nor the fragrance of flowers and incense, forasmuch as He is Himself perfect fragrance, needing nothing either within or without; but the noblest sacrifice to Him is for us to know who stretched out and vaulted the heavens…it does behoove us to offer a bloodless sacrifice and
the service of our reason.
Chapter 23 claims that idols actually have power, but that the power behind them is demonic. He cites Plato and Thales as supporters of this.
Chapter 26 claims that idols actually have the power of healing, but Chapter 27 modifies this view by saying that demons could see the future and they know when someone’s going to be healed naturally. Therefore, they do not actually bring about healing but rather they work on deceiving the mind of the person approaching the idol for healing. While I do not endorse this view, it is an interesting one as people claim that relics likewise bring healing and to many these relics are the modern version of pagan idols.
Chapter 31 speaks of our resurrected bodies being spiritual but still having flesh:
Sorry animal lovers, but he rejects the idea that animals will be in heaven:
[F]or God has not made us as sheep or beasts of burden, a mere by-work, and that we should perish and be annihilated.
Chapter 32 speaks of how Christians should kiss without lustful thoughts:
This line of thinking is part of his extreme view (possibly from pagan influence) that any sensual enjoyment whatsoever is wicked. In chapter 33 he says that marriage is only for procreation and that remarriage is adultery. He is making all of these claims in order to defend Christians against the charge that they are licentious.
In Chapter 34, Athenagoras precedes Tertullian in his condemnation of gladiatorial combat. He says that Christians don’t watch such combat, but the reason he emphasizes this is to protect Christians against the charge that they are murderers that eat human flesh. Obviously, this is a strange accusation to defend oneself against, especially against a group of people that hates violence so much that they won’t even watch it. Nonetheless, the allegation probably arose from the fact that early Christians taught the the bread and wine literally transformed into the body and blood of Christ.
On the Resurrection
Most of the letter is philosophical and generally does not cite the Bible at all. Rather, it addresses philosophical problems such as how does God resurrect bodies that have been destroyed and why God must resurrect the body and not simply the soul.
Chapter 12 appears to teach faith+works salvation:
[T]o those who bear upon them the image of the Creator Himself…the Creator has assigned perpetual duration in order that, recognising their own Maker, and His power and skill, and obeying law and justice, they may pass their whole existence free from suffering.
Chapter 14 appears to teach against original sin:
[I]f only a just judgment were the cause of the resurrection, it would of course follow that those who had done neither evil nor good— namely, very young children — would not rise again; but seeing that all are to rise again, those who have died in infancy as well as others, they too justify our conclusion that the resurrection takes place not for the sake of the judgment as the primary reason, but in consequence of the purpose of God in forming men, and the nature of the beings so formed.
Chapter 15 asserts that everyone resurrects because the human soul is eternal and made in the image of God. Because the human soul is only complete when it is fitted to a human body, then the body must ressurect for the soul to be properly eternal.
Chapter 18 quotes 2 Corinthian’s 5:10 in support of us being judged in the body for the good and bad we have done. This both gives us reason to believe in the bodily resurrection, and does imply to us that Athenagoras was portraying a works-righteousness system to the pagans.
Chapters 19 and 20 says that if there is no resurrection, then what point would there be in being virtuous? We might as well eat, drink, and be merry. Lewdness would not matter. Kant’s moral argument for God is given. Because morals are real, a God is real, and a just God necessitates a bodily resurrection.
The remainder of the letter continues fleshing out the culpability of the body during judgment, necessitating its resurrection.