And that it is from that region which is towards the south of the inheritance of Judah that the Son of God shall come, who is God, and who was from Bethlehem, where the Lord was born [and] will send out His praise through all the earth…
…Thus he indicates in clear terms that He is God, and that His advent was [to take place] in Bethlehem, and from Mount Effrem which is towards the south of the inheritance, and that [He is] man.
Irenaeus of Lyons
Against Heresies, Book III
Chapter XX
He who “was not born either by the will of the flesh, or by the will of man,” is the Son of man, this is Christ, the Son of the living God. For I have shown from the Scriptures, that no one of the sons of Adam is as to everything, and absolutely, called God, or named Lord. But that He is Himself in His own right, beyond all men who ever lived, God, and Lord, and King Eternal, and the Incarnate Word, proclaimed by all the prophets, the apostles, and by the Spirit Himself, may be seen by all who have attained to even a small portion of the truth. Now,
Irenaeus of Lyons
Against Heresies, Book III
Chapter XIX
To whom the Word says, mentioning His own gift of grace: “I said, Ye are all the sons of the Highest, and gods; but ye shall die like men.” He speaks undoubtedly these words to those who have not received the gift of adoption, but who despise the incarnation of the pure generation of the Word of God, defraud human nature of promotion into God, and prove themselves ungrateful to the Word of God, who became flesh for them. For it was for this end that the Word of God was made man, and He who was the Son of God became the Son of man, that man, having been taken into the Word, and receiving the adoption, might become the son of God. For by no other means could we have attained to incorruptibility and immortality, unless we had been united to incorruptibility and immortality. But how could we be joined to incorruptibility and immortality, unless, first, incorruptibility and immortality had become that which we also are, so that the corruptible might be swallowed up by incorruptibility, and the mortal by immortality, that we might receive the adoption of sons?
Irenaeus of Lyons
Against Heresies, Book III
Chapter XIX
For He is a most holy and merciful Lord, and loves the human race. Therefore, as I have already said, He caused man (human nature) to cleave to and to become, one with God. For unless man had overcome the enemy of man, the enemy would not have been legitimately vanquished. And again: unless it had been God who had freely given salvation, we could never have possessed it securely. And unless man had been joined to God, he could never have become a partaker of incorruptibility. For it was incumbent upon the Mediator between God and men, by His relationship to both, to bring both to friendship and concord, and present man to God, while He revealed God to man. For, in what way could we be partaken of the adoption of sons, unless we had received from Him through the Son that fellowship which refers to Himself, unless His Word, having been made flesh, had entered into communion with us?
Irenaeus of Lyons
Against Heresies, Book III
Chapter XVIII
For I have shown that the Son of God did not then begin to exist, being with the Father from the beginning; but when He became incarnate, and was made man, He commenced afresh the long line of human beings, and furnished us, in a brief, comprehensive manner, with salvation; so that what we had lost in Adam—namely, to be according to the image and likeness of God—that we might recover in Christ Jesus.
Irenaeus of Lyons
Against Heresies, Book III
Chapter XVIII
Wherefore also the Lord promised to send the Comforter,3620 who should join us to God. For as a compacted lump of dough cannot be formed of dry wheat without fluid matter, nor can a loaf possess unity, so, in like manner, neither could we, being many, be made one in Christ Jesus without the water from heaven.
Irenaeus of Lyons
Against Heresies, Book III
Chapter XVII
For error is plausible, and bears a resemblance to the truth, but requires to be disguised; while truth is without disguise, and therefore has been entrusted to children.
Irenaeus of Lyons
Against Heresies, Book III
Chapter XV
But while I bring out by these proofs the truths of Scripture, and set forth briefly and compendiously things which are stated in various ways, do thou also attend to them with patience, and not deem them prolix; taking this into account, that proofs [of the things which are] contained in the Scriptures cannot be shown except from the Scriptures themselves.
Irenaeus of Lyons
Against Heresies, Book III
Chapter XII
For this reason were four principal (καθολικαί) covenants given to the human race: one, prior to the deluge, under Adam; the second, that after the deluge, under Noah; the third, the giving of the law, under Moses; the fourth, that which renovates man, and sums up all things in itself by means of the Gospel, raising and bearing men upon its wings into the heavenly kingdom.
Irenaeus of Lyons
Against Heresies, Book III
Chapter XI
He [here] refers to the Father and the Son, and those who have received the adoption; but these are the Church. For she is the synagogue of God, which God—that is, the Son Himself—has gathered by Himself. Of whom He again speaks: “The God of gods, the Lord hath spoken, and hath called the earth.” Who is meant by God? He of whom He has said, “God shall come openly, our God, and shall not keep silence;” that is, the Son, who came manifested to men who said, “I have openly appeared to those who seek Me not.”
Irenaeus of Lyons
Against Heresies, Book III
Chapter VI