Gelasius of Cyzicus

Gelasius of Cyzicus was an ecclesiastical writer in the 5th century. The often attributed name Gelasius is an error of Photius I of Constantinople and of the editor of the editio princeps; the anonymous author never mentioned his name.

The anonymous author was the son of a priest of Cyzicus, and wrote in the Roman province of Bithynia in Asia Minor, about 475, to prove against the Eutychians, that the Nicene Fathers did not teach Monophysitism. These details he gives us in his preface. Beyond that nothing is known about his personality.

His "Syntagma" or collection of Acts of the First Nicene Council has hitherto been looked upon as the work of a sorry compiler; recent investigations, however, point to its being of some importance. It is divided into three books: book I treats of the Life of Constantine down to 323; book II of History of the Council in thirty-six chapters; of book III only fragments have been published.

The whole of book III was discovered by Cardinal Mai in the Ambrosian Library, and its contents are fully described by Oehler. The serious study of the sources of Gelasius may be said to have begun with Turner's identification of the long passages taken from Rufinus in book II. A complete analysis of the sources is in Löscheke, whose efforts it would appear, have restored to Gelasius a place among serious Church historians, of which he has been wrongly deprived and have also lent weight to the hitherto generally rejected idea that there was an official record of the Acts of the Council of Nicaea; and further that it was from this record that Dalmatius derived the opening discourse of Constantine, the confession of Hosius, the dialogue with Phaedo, and the nine dogmatic constitutions, which Hefele had pronounced "most certainly spurious".

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