Text ἄτρεπτον. Most mss. read σεπτόν. So, too, Greg. Naz., Orat. 34, from which these words are taken. An old interpretation is ‘venerabile est.’ But in the opinion of Combefis, Gregory’s text is corrupt, and ἄτρεπτονshould be read, which reading is also supported by various authorities, including three Cod. Reg.: cf. also De Trinit. in Cyril.