Essence–Energies distinction (Eastern Orthodox theology)

A real distinction between the essence (ousia) and the energies (energeia) of God is a central principle of Eastern Orthodox Christian theology. Orthodox theologians generally regard this distinction as more than merely conceptual. This doctrine is most closely identified with Gregory Palamas of Thessaloniki, who formulated it as part of his defense of the Athonite monastic practice of hesychasmos (the spiritual exercise of "stillness" to facilitate ceasless inner prayer and noetic contemplation of God) against the charge of heresy brought by the humanist scholar and theologian Barlaam of Calabria. These mystagogical teachings were approved in the Orthodox Church by a series of local Hesychast councils in the 14th century, and Gregory's commemoration during the liturgical season of Great Lent is seen as an extension of the Sunday of Orthodoxy.

Historically, Western Christian thought has tended to reject the essence-energies distinction as real in the case of God, characterizing the view as a heretical introduction of an unacceptable division in the Trinity and suggestive of polytheism. Further, the associated practice of hesychasm used to attain theoria or theosis was characterized as "magic". More recently, some Roman Catholic thinkers have taken a positive view of Palamite teachings, including how Gregory understood the essence-energies distinction, arguing that it does not represent an insurmountable theological division between Roman Catholicism and Eastern Orthodoxy.

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