Note (return) — Chapter V

"Filius dei filius hominis factus," "it is one and the same Jesus Christ, not a Jesus and a Christ, nor a mere temporary union of an æon and a man, but one and the same person, who created the world, was born, suffered, and ascended"—this along with the dogma of God the Creator is the cardinal doctrine of Irenæus:577 "Jesus Christ truly man and truly God" ("Jesus Christus, vere homo, vere deus").578 It is only the Church that adheres to this doctrine, for "none of the heretics hold the opinion that the Word of God became flesh" ("secundum nullam sententiam hæreticorum verbum dei caro factum est").579 What therefore has to be shown is (1) that Jesus Christ is really the Word of God, i.e., is God, (2) that this Word really became man and (3) that the incarnate Word is an inseparable unity. Irenæus maintains the first statement as well against the "Ebionites" as against the Valentinians who thought that Christ's advent was the descent of one of the many æons. In opposition to the Ebionites he emphasises the distinction between natural and adopted Sonship, appeals to the Old Testament testimony in favour of the divinity of Christ,580 and moreover argues that we would still be in the bondage of the old disobedience, if Jesus Christ had only been a man.581 In this connection he also discussed the birth from the virgin.582 He not only proved it from prophecy, but his recapitulation theory also suggested to him a parallel between Adam and Eve on the one hand and Christ and Mary on the other, which included the birth from the virgin.583 He argues in opposition to the Valentinians that it was really the eternal Word of God himself, who was always with God and always present to the human race, that descended.584 He who became man was not a being foreign to the world—this is said in opposition to Marcion—but the Lord of the world and humanity, the Son of God, and none other. The reality of the body of Christ, i.e., the essential identity of the humanity of Christ with our own, was continually emphasised by Irenæus, and he views the whole work of salvation as dependent on this identity.585 In the latter he also includes the fact that Jesus must have passed through and been subjected to all the conditions of a complete human life from birth to old age and death.586 Jesus Christ is therefore the Son of God who has really become the Son of man; and these are not two Christs but one, in whom the Logos is permanently united with humanity.587 Irenæus called this union "union of the Word of God with the creature" ("adunitio verbi dei ad plasma")588 and "blending and communion of God and man" ("commixtio et communio dei et hominis")589 without thereby describing it any more clearly.590 He views it as perfect, for, as a rule, he will not listen to any separation of what was done by the man Jesus and by God the Word.591 The explicit formula of two substances or natures in Christ is not found in Irenæus; but Tertullian already used it. It never occurred to the former, just because he was not here speaking as a theologian, but expressing his belief.592 In his utterances about the God-man Tertullian closely imitates Irenæus. Like the latter he uses the expression "man united with God" ("homo deo mixtus")593 and like him he applies the predicates of the man to the Son of God.594 But he goes further, or rather, in the interest of formal clearness, he expresses the mystery in a manner which shows that he did not fully realise the religious significance of the proposition, "the Son of God made Son of man" ("filius dei filius hominis factus"). He speaks of a "corporal and spiritual, i.e., divine, substance of the Lord", ("corporalis et spiritalis (i.e., divina) substantia domini")595 of "either substance of the flesh and spirit of Christ" ("utraque substantia et carnis et spiritus Christi"), of the "creation of two substances which Christ himself also possesses," ("conditio duarum substantiarum, quas Christus et ipse gestat")596 and of the "twofold condition not blended but united in one person—God and man" ("duplex status non confusus sed conjunctus in una persona—deus et homo".)597 Here we already have in a complete form the later Chalcedonian formula of the two substances in one person.598 At the same time, however, we can clearly see that Tertullian went beyond Irenæus in his exposition.599 He was, moreover, impelled to combat an antagonistic principle. Irenæus had as yet no occasion to explain in detail that the proposition "the Word became flesh" ("verbum caro factum") denoted no transformation. That he excludes the idea of change, and that he puts stress on the Logos' assumption of flesh from the Virgin is shown by many passages.600 Tertullian, on the other hand, was in the first place confronted by (Gnostic) opponents who understood John's statement in the sense of the Word's transforming himself into flesh, and therefore argued against the "assumption of flesh from the Virgin" ("assumptio carnis ex virgine");601 and, in the second place, he had to do with Catholic Christians who indeed admitted the birth from the Virgin, but likewise assumed a change of God into flesh, and declared the God thus invested with flesh to be the Son.602 In this connection the same Tertullian, who in the Church laid great weight on formulæ like "the crucified God," "God consented to be born" ("deus crucifixus," "nasci se voluit deus") and who, impelled by opposition to Marcion and by his apologetic interest, distinguished the Son as capable of suffering from God the Father who is impassible, and imputed to him human weaknesses—which was already a further step,—sharply emphasised the "distinct function" ("distincte agere") of the two substances in Christ and thus separated the persons. With Tertullian the interest in the Logos doctrine, on the one hand, and in the real humanity, on the other, laid the basis of that conception of Christology in accordance with which the unity of the person is nothing more than an assertion. The "deus factus homo" ("verbum caro factus") presents quite insuperable difficulties, as soon as "theology" can no longer be banished. Tertullian smoothed over these difficulties by juristic distinctions, for all his elucidations of "substance" and "person" are of this nature.