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 to
Theodosius. 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.
Works
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.
1. Comnmonitorium super nomine Coelestii
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.
2. Commonitorium adversus Haeresin Pelagii et Coelestii vel etiam
Scripta Juliani
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.
3. Refutatio Symmboli Theodori Mopsuestani
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.
Other Works
Of the following it will be enough to give the names :-- 4. Comparatio Dogmatum Pauli Samosateni et
Nestorii.5. Sermones V. Nestorii adversus Dei Genitricem
Mariam.6. Nestorii Epistola ad Cyrillum Alexandrinum.7. Cyrilli Alexandrini Epistola ad Nestorium.8. Cyrilli Alexandrini Epistola secunda ad
Nestorium.9. Cyrilli Alexandrini Epistola ad Clericos suos.10. Excerpta ex Codicibus Nestorii.11. Nestorii Sermones IV. adversus Haeresim
Pelagianam.12. Nestorii Epistola ad Coelestium.13. Nestorii Blasphemiarum Capitula, containing the
replies of Nestorius to the letters of Pope Coelestinus and Cyril of Alexandria.14. <title xml:lang="la">Synodus Ephesiana adversus
Nestorium, extracts from those proceedings of this council which were most
hostile to the views of Nestorius.15. Cyrilli Alexandrini Apologeticus adversus
Orientales.16. Cyrilli Alexandrini Apologeticus adversus
Theodoretum.17. Fragmenta Theodoreti, Diodori et Ibae.18. Eutherii Tyanensis Fragmentum.19. Nestorii Epistola ad Papam Coelestinum.20. Epistola Synodica Cyrilli ad Nestorium..21. Cyrilli Scholia de Incarnatione Unigeniti.
Lost Works
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.
Editions
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.
Further Information
A very full account of the labours of Garnier and Balllze will be found in Schönemann,
Bibl. Patrum Lat. vol. 2.16. See also Dupin, Ecclesiastical History of the Fifth Century; the preface of Garnier; and the
Prolegomena of Galland.