or by divine grace. By nature he is the Only-Begotten Son of God;^659 by adoption and grace he is
the First-Begotten Son of God.^660
The Adoptionists quoted in their favor mainly John 14:28Luke 1:80; 18:19; Mark 13:32;
John 1:14; 10:35; Rom. 8:29; 1 Cor. 11:3; 1 John 3:2; Deut. 18:15; Ps. 2: 8; 22:23, and other
passages from the Old Testament, which they referred to the Filius primogenitus et adoptivus; while
Ps. 60:4 (ex utero ante Luciferum genui te); 44:2; Is. 45:23; Prov. 8:25, were understood to apply
to the Filius unigenitus. None of these passages, which might as well be quoted in favor of Arianism,
bear them out in the point of dispute. Christ is nowhere called the "adopted" Son of God. Felix
inferred from the adoption of the children of God, that they must have an adoptive head. He made
use of the illustration, that as a son cannot have literally two fathers, but may have one by birth and
the other by adoption, so Christ, according to his humanity, cannot be the Son of David and the
Son of God in one and the same sense; but he may be the one by nature and the other by adoption.^661
It is not clear whether he dated the adopted Sonship of Christ from his exaltation^662 or fromhis baptism,^663 or already from his birth.^664 He speaks of a double birth of Christ, compares the
baptism of Christ with the baptism or regeneration of believers, and connects both with the spiritualis
generatio per adoptionem;^665 but, on the other hand, he seems to trace the union of the human nature
with the divine to the womb of the Virgin.^666
The Adoptionists, as already remarked, thought themselves in harmony with the Christology
of Chalcedon, and professed faith in one divine person in two full and perfect natures;^667 they only
wished to bring out their views of a double Sonship, as a legitimate consequence of the doctrine
of two natures.
The champions of orthodoxy, among whom Alcuin, the teacher and friend of Charlemagne,
was the most learned and able, next to him Paulinus of Aquileja, and Agobard of Lyons, unanimously
viewed Adoptionism as a revival or modification of the Nestorian heresy, which was condemned
by the third Oecumenical Council (431).^668
Starting from the fact of a real incarnation, the orthodox party insisted that it was the eternal,
only begotten Son of God, who assumed human nature from the womb of the Virgin, and united
it with his divine person, remaining the proper Son of God, notwithstanding this change.^669 They
quoted in their favor such passages as John 3:16; Rom. 8:32; Eph. 5:2; Acts 3:13–15.
(^659) Unigenitus,μονογενής, John 1: 14, 18.
660
Primogenitus,πρωτότοκοςἐν πολλοι̑ςἀδελφοι̑ς,, Rom. 8:29; Comp. Col. 1:15.
(^661) Alcuin, Contra Felicem, I. 12, and III. 1.
(^662) Dorner, II. 319.
(^663) Walch.
(^664) Neander.
(^665) l.c. II. 15.
(^666) l.c. V. 1.
(^667) "In una persona, duabus quoque naturis plenis atque perfectis." Alcuin, Opp. II. 567.
(^668) Alcuin, contra Felicem, lib. l.c. 11: "Sicut Nestoriana impietas in duas Christum dividit personas propter duas naturas;
ita et vestra indocta temeritas in duos eum dividit filios, unum proprium, alterum adoptivum. Si vero Christus est proprius
Filius Dei Patris et adoptivus, ergo est alter et alter," etc. Lib. IV. c. 5: "Nonne duo sunt, qui verus est Deus, et qui nuncupativus
Deus? Nonne etiam et duo sunt, qui adoptivus est Filius, et ille, qui verus est Filius?"
(^669) Ibid. II. 12: "Nec in illa assumptione alius est Deus, alius homo, vel alius Filius Dei, et alius Filius Virginis; sed idem
est Filius Dei, qui et Filius Virginis; ut sit unus Filius etiam proprius et perfectus in duabus naturis Dei et hominis." In the