Baring-Gould’s sources: Greek Menæa. Authority:—The Chronicon Alexandrinum, or Chron. Paschale, under date 269 from the Ascension, which is equivalent to 297 of the vulgar era. In this Chronicle he is called Gelasinus. Theodoret may, perhaps, allude to him, when he says that some have passed from the stage of the theatre to the ranks of the martyrs. Du curand Græc. Affect., Serm. 8. Much the same circumstances are related of S. Genesius (Aug. 25th), who suffered about 286, unless both are the same; Gelasius in the West becoming Genesius by a slight change of liquids.

Gelasius was a comic actor, the second clown of the theatre at Heliopolis, in Phœnicia. One day, on the stage was performed a parody of Christian rites for the amusement of the heathen spectators. A large bathing tub was introduced on the stage, filled with warm water, and the clown, Gelasius, was dipped in it, the other clown pronouncing over him the sacramental words. When he rose from the bath, and was vested in white, it was observed that a change had come over him; the jesting air and laugh were gone, and a solemn expression had overspread his countenance. "I am a Christian," said he; "in the font I saw a dazzling light. Therefore, I will die as a Christian." As soon as the audience became aware that he spoke in sober earnest, the theatre became a scene of wild tumult, the people deserted their seats, and rushed on the stage, and dragged the poor actor forth, clothed in his white robe, and stoned him to death outside the theatre. His body was transported to the village of Mariamnia, near Heliopolis, of which he was a native, and an oratory was erected by the Christians over his tomb.