distinguished among ecclesiastical writers as a most zealous antagonist of the Pelagians and the Nestorians, appears to have commenced his literary career during the pontificate of Zosimus, A. D. 218, at Rome.
There he drew up a discourse against the opinions of Coelestius, which he transmitted to Africa and received in reply an epistle from St. Augustin, still extant (Ep.
cxciii. ed. Bened.). Having repaired to Constantinople about ten years afterwards, for the purpose of counteracting the designs of the banished Julianus [JULIANIUS DIDIUS], he presented his Commonitorium
He then became deeply involved in the controversy regarding the Incarnation, and in this found active occupation for the remainder of his life, which must have extended beyond the middle of the fifth century, since we find mention made in his writings of the Eutychians, whose name does not appear among the catalogue of heretics, until after the council of Chalcedon, held in 451. Mercator seems undoubtedly to have been a layman, but we are absolutely ignorant of every circumstance connected with his origin and personal history. Hence, in the absence of all ascertained facts, an ample field is thrown open for that unprofitable species of labour which seeks to create substance out of shadow; and here the exertions of Garnier and Gabriel Gerberon are especially conspicuous, but it would be a mere waste of time and space to recount their visions.
The works of Mercator refer exclusively to the Pelagian and Nestorian heresies, and consist for the most part, in so far as the latter is concerned, of passages extracted and translated from the chief Greek authorities upon both sides, and arranged in such a manner as to enable the orthodox to comprehend the doctrines advanced by their opponents, and the arguments by which they were confuted.
composed originally in Greek, presented in 429 to the emperor Theodosius, and translated into Latin some years afterwards.
The object of this piece was to procure the expulsion of Julianus and Coelestius from Constantinople, by giving a history of the rise and progress of their errors, and by exposing the fatal tendency of their doctrines. We learn fRom the full title that this end was accomplished, and that the two hierarchs, with their followers, were banished by an imperial edict, and subsequently condemned in the Council of Ephesus (231) by the judgment of 275 bishops.
Made up of excerpts from the writings of Julianus, with answers (subnotationes
) annexed by Mercator. Garnier gives to this production the title Liber Subnotationum ad Pieritium Presbyteruzn,
and considers it as consisting of two parts, the first, or Commonitorium,
being a preface or introduction; the second, or Subnotationes ad Verba Juliani, forming the main body of the work.
An examination of the false doctrine with regard to the Nature of Christ, contained in a creed attributed to Theodorus of Mopsuestia, the friend and supporter of Julianus.
Of the following it will be enough to give the names :--
Among the lost works of this author we may reckon the Libri contra Pelagianos,
of which we hear in the epistle of St. Augustin (cxciii.). Dupin hazards a conjecture that the Hypognosticon,
commonly attributed to the bishop of Hippo, may be in reality the treatise in question.
It is remarkable that no ancient writer, if we except St. Augustine in the letter named above, takes any notice of Mercator, who remained altogether unknown until the seventeenth century, when Holstein discovered a MS. of his works in the Vatican, and soon after a second was found by Labbe, in the library of the Chapter of Beauvais. Labbe printed the Coemmonitorium super Nomine Coelestii, in his collection of councils, fol. Paris, 1671, vol. ii. pp. 1512-1517
; a selection from the Vatican MS. was published by Gabriel Gerberon, a Benedictine, under the assumed name of Righerius, 12mo. Brux. 1673
, and in the same year the first complete edition appeared at Paris in folio, under the editorial inspection of the learned Garnier, the text being formed upon a comparison of the only two existing MSS. The most esteemed edition is that of Baluze, 8vo. Par. 1684, reprinted with additions and corrections, by Galland, in his Bibliotheca Patrum, vol. viii. pp. 615-737, fol. Venet. 1772.
A very full account of the labours of Garnier and Balllze will be found in Schönemann, Bibl. Patrum Lat.
See also Dupin, Ecclesiastical History of the Fifth Century;
the preface of Garnier; and the Prolegomena of Galland.