Irenaeus and canon of New Testament
Irenæus (c. 115 to 202) was born in Smyrna (in present day Turkey), studied in Rome before going to Lyons and served as bishop. His main work is Against Heresies or Adversus hareses in five volumes, an analytical refutation against Gnosticism. He did not give us list of New Testament books but from Against Heresies we know that he quoted or alluded to four Gospels, Acts, Paul’s epistles (except Philemon), Hebrews, 1 Peter, 1 & 2 John, James, Jude and Revelation (based on scriptural reference in footnotes of Philip Schaff: Anti Nicene Fathers). He was the first to limit Gospel only to four we know today: Matthew, Mark, Luke and John.
It is not possible that the Gospels can be either more or fewer in number than they are. For, since there are four zones of the world in which we live, and four principal winds, while the Church is scattered throughout all the world, and the “pillar and ground” of the Church is the Gospel and the spirit of life; it is fitting that she should have four pillars, breathing out immortality on every side, and vivifying men afresh. From which fact, it is evident that the Word, the Artificer of all, He that sitteth upon the cherubim, and contains all things, He who was manifested to men, has given us the Gospel under four aspects, but bound together by one Spirit. As also David says, when entreating His manifestation, “Thou that sittest between the cherubim, shine forth.” For the cherubim, too, were four-faced, and their faces were images of the dispensation of the Son of God. For, [as the Scripture] says, “The first living creature was like a lion,” symbolizing His effectual working, His leadership, and royal power; the second [living creature] was like a calf, signifying [His] sacrificial and sacerdotal order; but “the third had, as it were, the face as of a man,”-an evident description of His advent as a human being; “the fourth was like a flying eagle,” pointing out the gift of the Spirit hovering with His wings over the Church.
Irenæus, Against Heresies 3.11.8
Irenæus also considered Shepherd of Hermas as scripture and had high regard of 1 Clement.
Truly, then, the Scripture [Shepherd of Hermas] declared, which says, “First of all believe that there is one God, who has established all things, and completed them, and having caused that from what had no being, all things should come into existence: “He who contains all things, and is Himself contained by no one.
Irenæus, Against Heresies 4.20.2
In the time of this Clement, no small dissension having occurred among the brethren at Corinth, the Church in Rome despatched a most powerful letter to the Corinthians, exhorting them to peace, renewing their faith, and declaring the tradition which it had lately received from the apostles, proclaiming the one God, omnipotent, the Maker of heaven and earth, the Creator of man, who brought on the deluge, and called Abraham, who led the people from the land of Egypt, spake with Moses, set forth the law, sent the prophets, and who has prepared fire for the devil and his angels. From this document, whosoever chooses to do so, may learn that He, the Father of our Lord Jesus Christ, was preached by the Churches, and may also understand the apostolical tradition of the Church, since this Epistle is of older date than these men who are now propagating falsehood, and who conjure into existence another god beyond the Creator and the Maker of all existing things.
Irenæus, Against Heresies 3.3.3
In his work we also find Agrapha, i.e. words of Christ not found in four Gospels.
The predicted blessing, therefore, belongs unquestionably to the times of the kingdom, when the righteous shall bear rule upon their rising from the dead; when also the creation, having been renovated and set free, shall fructify with an abundance of all kinds of food, from the dew of heaven, and from the fertility of the earth: as the elders who saw John, the disciple of the Lord, related that they had heard from him how the Lord used to teach in regard to these times, and say: The days will come, in which vines shall grow, each having ten thousand branches, and in each branch ten thousand twigs, and in each true twig ten thousand shoots, and in each one of the shoots ten thousand dusters, and on every one of the clusters ten thousand grapes, and every grape when pressed will give five and twenty metres of wine. And when any one of the saints shall lay hold of a cluster, another shall cry out, “I am a better cluster, take me; bless the Lord through me.” In like manner [the Lord declared] that a grain of wheat would produce ten thousand ears, and that every ear should have ten thousand grains, and every grain would yield ten pounds of clear, pure, fine flour; and that all other fruit-bearing trees, and seeds and grass, would produce in similar proportions; and that all animals feeding [only] on the productions of the earth, should [in those days] become peaceful and harmonious among each other, and be in perfect subjection to man.
Irenæus, Against Heresies, 5.33.3
What he quoted here is a fragment of five books (now lost) of Expositions of the Oracles of the Lord, written in c. 130 AD by Papias, bishop of Hierapolis in Phyrgia in early second century AD.