Gregorios 28 was bishop of Theodoropolis in Europa; in 787 he attended the Second Council of Nikaia (the Seventh Ecumenical Council) and was probably present at all eight sessions, from 24 September to 23 November 787: Mansi XII 995-XIII 486. In the lists of those present at the first and seventh sessions he is styled Γρηγορίου ἐπισκόπου Θεοδωρουπόλεως: Mansi XII 995, XIII 368. Elsewhere he is styled Γρηγόριος ὁ ὁσιώτατος ἐπίσκοπος Θεοδωρουπόλεως or similar: Mansi XII 1099, XIII 144, XIII 388. At the second session he supported the traditional veneration of icons as described in statements from pope Hadrian I (Hadrianos 1) and condemned iconoclasts: Mansi XII 1099. At the fourth session he subscribed statements read out from the Fathers in support of the veneration of icons: Mansi XIII 144. At the seventh session he subscribed the statement of the faith adopted by the Council: Mansi XIII 388.

(Publishable link for this person: )