AMMONIUS. - Alexandrian ecclesiastical writer of the time of Origen. Eusebius (Hist. eccl., VI, 19, 9-10) and after him St. Jerome praise his writings, but mistakenly confuse him with Ammonius Saccas, the teacher of Origen.
He wrote a book On the Agreement between Jesus and Moses, directed against the Gnostics and Manicheans. It is not certain that he is to be identified with the Alexandrian Ammonius to whom Eusebius (and perhaps also Maruthas of Maipherqat) elsewhere attributes a Gospel synopsis, the very one on which he based his Gospel canons; nor is it certain that he is the same as A., bishop of Thmuis.
BIBL.: St. Jerome, De viris illustribus, 55; O. Bardenhewer, Geschichte der altkirchlichen Literatur, I, 2nd ed., Freiburg im Br. 1914, p. 198; A. Harnack, Geschichte der altkirchlichen Literatur, I, Leipzig 1893, p. 406; II, ibid. 1897, p. 81.