St. Gregory Palamas (Greek: Γρηγόριος Παλαμάς; 1296–1359) – was a monk of Mount Athos in Greece and later the archbishop of Thessaloniki, known as a preeminent theologian of Hesychasm. The teachings embodied in his writings defending Hesychasm against the attack of Barlaam are sometimes referred to as Palamism, and his followers as Palamites.
“Since the Son of God, in his incomparable love for man, did not only unite His divine Hypostasis with our nature, by clothing Himself in a living body and a soul gifted with intelligence… but also united himself… with the human hypostases themselves, in mingling himself with each of the faithful by communion with his Holy Body, and since he becomes one single body with us (cf. Eph. 3:6), and makes us a temple of the undivided Divinity, for in the very body of Christ dwelleth the fullness of the Godhead bodily (Col. 2:9), how should he not illuminate those who commune worthily with the divine ray of His Body which is within us, lightening their souls, as He illumined the very bodies of the disciples on Mount Thabor? For, on the day of the Transfiguration, that Body, source of the light of grace, was not yet united with our bodies, it illuminated from outside those who worthily approached it, and sent the illumination into the soul by an intermediary of the physical eyes; but now, since it mingled with us and exists in us, it illuminates the soul from within.”
~ from: Triads I.iii.38.