Suppose there arise a dispute relative to some important question among us, should we not have recourse to the most ancient Churches with which the apostles held constant intercourse, and learn from them what is certain and clear in regard to the present question? For how should it be if the apostles themselves had not left us writings? Would it not be necessary, in that case, to follow the course of the tradition which they handed down to those to whom they did commit the Churches?
Irenaeus of LyonsA man that is an heretic, after the first and second admonition, reject; knowing that he that is such is subverted, and sinneth, being condemned of himself.
Irenaeus of LyonsOthers of them employ outward marks ... They style themselves Gnostics. They also possess images, some of them painted and others formed from different kinds of material. They maintain that a likeness of Christ was made by Pilate at that time when Jesus lived among them. They crown these images, and set them up along with the images of the philosophers of the world, such as Pythagoras, Plato, and Aristotle, and the rest. They have also other modes of honoring these images just like the Gentiles.
Irenaeus of LyonsThrough a tree we were made debtors to God; so through a tree we have our debt canceled.
Irenaeus of LyonsSince it is impossible, without God, to come to knowledge of God, he teaches men through his Word to know God.
Irenaeus of LyonsError never shows itself in its naked reality, in order not to be discovered. On the contrary, it dresses elegantly, so that the unwary may be led to believe that it is more truthful than truth itself.
Irenaeus of LyonsHe [Jesus] fought and conquered. On the one hand, he was man who struggled for his fathers and through his obedience cancelled their disobedience. On the other hand, he bound the strong one and freed the weak and bestowed salvation on his handiwork by abolishing sin. For he is our compassionate and merciful Lord who loves mankind ... Had not man conquered man's adversary, the enemy would not have been conquered justly. Again, had it not been God who bestowed salvation we would not possess it securely.
Irenaeus of Lyons