le optimism in contrast to Gnostic pessimism, brought
Irenaeus into touch with certain Pauline trains of thought,[485] and
enabled him to adhere to the theology of the Apologists. At the same
time it opened up a view of the person of Christ, which supplemented the
great defect of that theology,[486] surpassed the Christology of the
Gnostics,[487] and made it possible to utilise the Christological
statements contained in certain books of the New Testament.[488]

So far as we know at least, Irenaeus is the first ecclesiastical
theologian after the time of the Apologists (see Ignatius before that)
who assigned a quite specific significance to the person of Christ and
in fact regarded it as the vital factor.[489] That was possible for him
because of his realistic view of redemption. Here, however, he did not
fall into the abyss of Gnosticism, because, as a disciple of the
"elders", he adhered to the early-Christian eschatology, and because, as
a follower of the Apologists, he held, along with the realistic
conception of salvation, the other dissimilar theory that Christ, as the
teacher, imparts to men, who are free and naturally constituted for
fellowship with God, the knowledge which enables them to imitate God,
and thus by their own act to attain communion with him. Nevertheless to
Irenaeus the pith of the matter is already found in the idea that
Christianity is real redemption, i.e., that the highest blessing
bestowed in Christianity is the deification of human nature through the
gift of immortality, and that this deification includes the full
knowledge and enjoying of God (visio dei). This conception suggested to
him the question as to the cause of the incarnation as well as the
answer to the same. The question "cur deus--homo", which was by no means
clearly formulated in the apologetic writings, in so far as in these
"homo" only meant _appearance_ among men, and the "why" was answered by
referring to prophecy and the necessity of divine teaching, was by
Irenaeus made the central point. The reasons why the answer he gave was
so highly satisfactory may be stated as follows: (1) It proved that the
Christian blessing of salvation was of a specific kind. (2) It was
similar in point of form to the so-called Gnostic conception of
Christianity, and even surpassed it as regards the promised extent of
the sphere included in the deification. (3) It harmonised with the
eschatological tendency of Christendom, and at the same time wa