CABASILAS, NICHOLAS. – A celebrated Byzantine theologian of the fourteenth century (d. after 1396), whose life is almost unknown, but whose works, remarkable for several reasons, have been the subject of numerous recent studies. Some authors have confused him both with his uncle, Nilus C. (q.v.), of whom he would allegedly have been the successor in the see of Thessalonica—a claim without foundation—and with Michael C. the Sacellarius, his contemporary (cf. S. Salaville, C. le Sacellaire et N. C., in *Echos d’Orient*, 35 [1936], pp. 421-27). In fact, we have no proof that he belonged to either the secular or the regular clergy. In the Palamite controversy, he sided with Gregory Palamas, as attested by the unpublished pamphlet *Adversus Gregoras deliramenta* in Paris. gr. 1213, ff. 282-84v.; yet he was a moderate Palamite. He was also anti-Latin and inaugurated the controversy between Greeks and Latins over the form of the Eucharist and the question of the epiclesis (cf. chaps. 29 and 30 of his *Explanation of the Byzantine Mass*: PG 150, 429-37). Moreover, he was influenced by Latin theology, which he encountered through the Greek translation of the two *Summae* of St. Thomas, made by his friend Demetrius Cydones, who had converted to Catholicism.
The list of C.’s writings, only partially published, has not yet been fully compiled. They consist chiefly of treatises on spirituality, homilies and parenetic works, letters, and epigrams. The principal ones are gathered in Paris. gr. 1213 (15th c.). Among the published works, the following deserve mention: *De vita in Christo* (PG 150, 493-627), a treatise, and one of the best, on the spiritual life; the *Explanation of the Byzantine Mass* (PG 150, 368-492), a work highly esteemed by liturgists; the *Odes on the Nativity, the Annunciation, and the Dormition of the Blessed Virgin*, edited by M. Jugie (PO 19, 405-510; cf. id., *La dottrina mariale di N. C.*, in *Echos d’Orient*, 18 [1919], pp. 373-88). For other published writings of C., see I. Ehrhard in Krumbacher’s *Geschichte der byzant. Literatur*, 2nd ed., Munich, 1897, p. 159, and PG 150; to be supplemented by the following publications: *Panegyrique de Matthieu Cantacuzène et Anne Paléologue*, ed. M. Jugie, in *Bollettino dell’Istituto archeologico russo di Costantinopoli*, 15 (1911), pp. 112-21; *Prière inédite à Jésus Christ*, ed. S. Salaville, in *Echos d’Orient*, 35 (1936), pp. 43-50.