Whether Christ Is One or Two?
Objection 1: It would seem that Christ is not one, but two. For
Augustine says (De Trin. i, 7): "Because the form of God took the
form of a servant, both are God by reason of God Who assumed, yet
both are Man by reason of the man assumed." Now "both" may only be
said when there are two. Therefore Christ is two.
Obj. 2: Further, where there is one thing and another there are two.
Now Christ is one thing and another; for Augustine says (Enchiridion
xxxv): "Being in the form of God . . . He took the form of a servant
. . . being both in one; but He was one of these as Word, and the
other as man." Therefore Christ is two.
Obj. 3: Further, Christ is not only man; for, if He were a mere man,
He would not be God. Therefore He is something else than man, and
thus in Christ there is one thing and another. Therefore Christ is
two.
Obj. 4: Further, Christ is something that the Father is, and
something that the Father is not. Therefore Christ is one thing and
another. Therefore Christ is two.
Obj. 5: Further, as in the mystery of the Trinity there are three
Persons in one Nature, so in the mystery of the Incarnation there are
two natures in one Person. But on account of the unity of the Nature,
notwithstanding the distinction of Person, the Father and Son are
one, according to John 10:30: "I and the Father are one." Therefore,
notwithstanding the unity of Person, Christ is two on account of the
duality of nature.
Obj. 6: Further, the Philosopher says (Phys. iii, text. 18) that
"one" and "two" are predicated denominatively. Now Christ has a
duality of nature. Therefore Christ is two.
Obj. 7: Further, as accidental form makes a thing otherwise
(_alterum_) so does substantial form make another thing (_aliud_) as
Porphyry says (Praedic.). Now in Christ there are two substantial
natures, the human and the Divine. Therefore Christ is one thing and
another. Therefore Christ is two.
_On the contrary,_ Boethius says (De Duab. Nat.): "Whatever is,
inasmuch as it is, is one." But we confess that Christ is. Therefore
Christ is one.
_I answer that,_ Nature, considered in itself, as it is used in the
abstract, cannot truly be predicated of the suppositum or person,
except in God, in Whom "what it is" and "whereby it is" do not
differ, as stated in the First Part (Q. 29, A. 4, ad 1). But in
Christ, since there are two natures, viz. the Divine and the human,
one of them, viz. the Divine, may be predicated of Him both in the
abstract and in the concrete, for we say that the Son of God, Who is
signified by the word Christ, is the Divine Nature and is God. But
the human nature cannot be predicated of Christ in the abstract, but
only in the concrete, i.e. as it is signified by the suppositum. For
we cannot truly say that "Christ is human nature," because human
nature is not naturally predicated of its suppositum. But we say that
Christ is a man, even as Christ is God. Now God signifies one having
the Godhead, and man signifies one having manhood. Yet one having
manhood is differently signified by the word "man" and by the word
"Jesus" or "Peter." For this word "man" implies one having manhood
indistinctly, even as the word "God" implies indistinctly one having
the Godhead; but the word "Peter" or "Jesus" implies one having
manhood distinctly, i.e. with its determinate individual properties,
as "Son of God" implies one having the Godhead under a determinate
personal property. Now the dual number is placed in Christ with
regard to the natures. Hence, if both the natures were predicated in
the abstract of Christ, it would follow that Christ is two. But
because the two natures are not predicated of Christ, except as they
are signified in the suppositum, it must be by reason of the
suppositum that "one" or "two" be predicated of Christ.
Now some placed two supposita in Christ, and one Person, which, in
their opinion, would seem to be the suppositum completed with its
final completion. Hence, since they placed two supposita in Christ,
they said that God is two, in the neuter. But because they asserted
one Person, they said that Christ is one, in the masculine, for the
neuter gender signifies something unformed and imperfect, whereas the
masculine signifies something formed and perfect. On the other hand,
the Nestorians, who asserted two Persons in Christ, said that Christ
is two not only in the neuter, but also in the masculine. But since
we maintain one person and one suppositum in Christ, as is clear from
Q. 2, AA. 2, 3, it follows that we say that Christ is one not merely
in the masculine, but also in the neuter.
Reply Obj. 1: This saying of Augustine is not to be taken as if
"both" referred to the predicate, so as to mean that Christ is both;
but it refers to the subject. And thus "both" does not stand for two
supposita, but for two words signifying two natures in the concrete.
For I can say that "both, viz. God and Man, are God" on account of
God Who assumes; and "both, viz. God and Man," are Man on account of
the man assumed.
Reply Obj. 2: When it is said that "Christ is one thing and another,"
this saying is to be explained in this sense--"having this nature and
another." And it is in this way that Augustine explains it (Contra
Felic. xi), where, after saying, "In the mediator of God and man, the
Son of God is one thing, and the Son of Man another," he adds: "I say
another thing by reason of the difference of substance, and not
another thing by reason of the unity of person." Hence Gregory
Nazianzen says (Ep. ad Chelid. ci): "If we must speak briefly, that
of which the Saviour is, is one thing and another; thus the invisible
is not the same as the visible; and what is without time is not the
same as what is in time. Yet they are not one and another: far from
it; for both these are one."
Reply Obj. 3: This is false, "Christ is only man"; because it does
not exclude another suppositum, but another nature, since terms
placed in the predicate are taken formally. But if anything is added
whereby it is drawn to the suppositum, it would be a true
proposition--for instance, "Christ is only that which is man."
Nevertheless, it would not follow that He is "any other thing than
man," because "another thing," inasmuch as it refers to a diversity
of substance, properly refers to the suppositum, even as all relative
things bearing a personal relation. But it does follow: "Therefore He
has another nature."
Reply Obj. 4: When it is said, "Christ is something that the Father
is"; "something" signifies the Divine Nature, which is predicated
even in the abstract of the Father and Son. But when it is said:
"Christ is something that is not the Father"; "something" signifies,
not the human nature as it is in the abstract, but as it is in the
concrete; not, indeed, in a distinct, but in an indistinct
suppositum, i.e. inasmuch as it underlies the nature and not the
individuating properties. Hence it does not follow that Christ is one
thing and another, or that He is two, since the suppositum of the
human nature in Christ, which is the Person of the Son of God, does
not reckon numerically with the Divine Nature, which is predicated of
the Father and Son.
Reply Obj. 5: In the mystery of the Divine Trinity the Divine Nature
is predicated, even in the abstract of the three Persons; hence it
may be said simply that the three Persons are one. But in the mystery
of the Incarnation both natures are not predicated in the abstract of
Christ; hence it cannot be said simply that Christ is two.
Reply Obj. 6: Two signifies what has duality, not in another, but in
the same thing of which "two" is predicated. Now what is predicated
is said of the suppositum, which is implied by the word "Christ."
Hence, although Christ has duality of nature, yet, because He has not
duality of suppositum, it cannot be said that Christ is two.
Reply Obj. 7: Otherwise implies diversity of accident. Hence
diversity of accident suffices for anything to be called "otherwise"
simply. But "another thing" implies diversity of substance. Now not
merely the nature, but also the suppositum is said to be a substance,
as is said _Metaph._ v, text. 15. Hence diversity of nature does not
suffice for anything to be called "another thing" simply, unless
there is diversity of suppositum. But diversity of nature makes
"another thing" relatively, i.e. in nature, if there is no diversity
of suppositum.
_______________________