MARCELLUS of ANCYRA. - Bishop of Ancyra (Ankara), d. ca. 374, known in the history of the 4th century for having, in the struggle against Arianism and with the intent of safeguarding the consubstantiality of the divine Persons, so insisted on the unity of God as to stray into modalism (v.), denying the real distinction of the Persons themselves.
In 314 he attended as bishop the Council of Ancyra (Mansi, II, p. 534). In 325 he was present at the Council of Nicaea, where he sided with Athanasius, opposing the Arians (Athanasius, Apol. c. ar., 23: PG 25, 288). In 335 at Tyre and Jerusalem he opposed the deposition of Athanasius and the readmission of Arius. About the same time he wrote against the Seminary of Asterius his major work (original title doubtful), of which Eusebius of Caesarea preserved several fragments in his refutation (Contra Marcellum: De ecclesiastica theologia). In 336 a Synod of Constantinople, composed mostly of Arianizers, condemned M.'s work as heretical, anathematized M. himself, and, probably already at that time, deposed him; he was reproached for being infected with Sabellianism, for teaching that the Son of God had a beginning with the birth of Mary and that His kingdom would end with the end of the world (Sozomen, Hist. eccl., II, 33: PG 67, 1028 sg.). After the death of Constantine (337) he returned for a short time to Ancyra, where disturbances took place (Athanasius, Apol. c. ar., 33: PG 25, 304). In 338-39 he was again condemned by a Synod of Constantinople and accused at Rome (ibid., 32, 301). He wrote a letter to Pope Julius I (Epiphanius, Haer., 72, 2: ibid., 42, 384-88); in the summer of 339 he was in Rome, where he obtained absolution from a Roman synod (Athanasius, Apol. c. ar., 20, 32: PG, 25, 280; 301). In 342-43 he was present at the Synod of Sardica and was again condemned by the Arian faction (Hilary, frg. 3: PL 10, 658 sg.), but absolved by the Westerners (ibid. 2, 636-38). In the following years he suffered further repeated condemnations from the Easterners, especially at the Synod of Antioch in 345, in the so-called macrostic or long formula (L. Hahn, Bibliothek der Symbolen, Breslau 1879, § 159 n. 6, p. 194), in which he was condemned along with Paul of Samosata, to whom he was likened, and his own disciple Photinus, bishop of Sirmium and frankly Sabellian. Athanasius himself, informed by the case of Photinus of the dangers of M.'s theology, abandoned him, though always with a certain restraint toward the old friend (Hilary, frg. 2, 21: PL 10, 650 sg.; Epiphanius, Haer., 72, 4: PG 42, 388). The Westerners did not yet seem to concern themselves with M. (Hilary, frg. 2, 22: PL 10, 651), which provoked the complaints of St. Basil (Ep. 69, 2: PG 32, 432). Epiphanius (Haer., 72, 1: ibid., 42, 381) makes M. live until ca. 374; but it is not known how he spent the last decades of his life. Only around 380, Pope Damasus, without naming him, condemned his doctrines (Anathematism, 8: Mansi, III, p. 483 A; Theodoret, Hist. eccl., V, 11, 5: PG 82, 1221), while the Council of Constantinople (381) condemned him by name in its first canon (Mansi, III, p. 560 A).
If the notice of Jerome (De viris ill., 86: PL 23, 729) is correct, M. wrote several works, especially against the Arians. None, however, have come down to us; but Martin (op. cit. in bibl.) has recently attributed to him the work De ecclesia which passes under the name of Antimus of Antioch (ed. G. Mercati [Studi e testi, 5], Rome 1905, pp. 87-98). M.'s theory, expressed in complicated and subtle formulas, is a certain modalism (v.) or monarchian Trinitarianism, with Adoptionist hues, in which the Persons of the Trinity are only different manifestations of a single Person according to the different phases of the economy of salvation, and there is a tendency to make of Christ a mere man in whom the divine power dwells. Against the danger of an Arianism of a polytheistic hue, M. insists above all on the concept of God as absolute unity (ἐννέας), a single prosopon, the Father; who indeed eternally has in Himself a Logos, but this is not a distinct Person, but only an active force (ἐνέργεια) of the single prosopon; and in this sense M. understands the homoousios between the Father and the Word. At the moment of the creation of the world this Logos proceeds (προέρχεται) from the Father, externalizing itself as ἐνέργεια διαστικῆς of the single prosopon, through a certain dilation (πλατυσμός, ἐκτασμός) which, however, introduces no distinction of Persons into God. In the Incarnation this Logos becomes the Son; not that a true generation in God occurs then, but only because the flesh of Christ is generated by the Virgin, and in this flesh the divine ἐνέργεια, which is always ἐννέας in the Father, is the principle of all operations. Just as the Logos was in God before creation, so the Spirit was in the Logos before Christ, after the Resurrection (John 20:22), communicated it to the Apostles, and only from this moment, proceeding from the Father and the Son, it externalized itself as an active force in the Church of the single divine prosopon. Thus: the Monad has extended itself into a Triad (frg. 67: ed. E. Klostermann, p. 197, 32 sg.). At the end of the world that operative force which has extended from the single Monad will be reabsorbed into it, and thus will end the kingdom, not of the Logos, but of Christ (1 Cor 15:28) and of the Spirit. It is against this last point of doctrine that the anti-Marcellan professions of faith and the symbols explicitly added the concept of Luke 1:33: *cuius regni non erit finis*.
Loofs at one time attempted, not without subsequent variations and uncertainties, to present M., together with Paul of Samosata, as a representative of what would have been the primitive genuine Christian doctrine, a kind of modalist and Adoptionist monarchianism. The essential methodological fallacy of Loofs lies in considering as "Christian" doctrine opinions expressed at some point by "Christians," without taking into account either their relationship to the overall data of Scripture or the reactions of the responsible spheres of doctrine in the Church—bishops and Roman pontiffs—even when these expressly condemned such opinions as misleading. M.'s doctrine is essentially, although with its own nuances, the old modalist error, which had already been condemned by the Church many times before. This shows that, in M.'s case, the Westerners hesitated for a long time, the reason for which is to be sought not in any secret connivance of doctrine, but in their not having immediately understood its true meaning, both because of the skillful oral defense that M. was able to make with complicated and subtle formulas, with protests that it was only hypothetical opinions and not absolute affirmations (cf. Hilary, frg. 2: PL 10, 636), and because of the benevolence that his person long enjoyed among his former companions in the struggle against Arianism.