The Energies of God are a central principle of theology in the Eastern Orthodox Church.

The principle is that God's Essence (ousia) is distinct from His Energies (energeiai) or activities in the world, and it is the energies that enable us to experience something of the Divine. Orthodox theology holds that while we can never know God as He is in Himself ("Essence") and that direct experience of God would simply obliterate us (much as Moses could not survive seeing God's face), God's "Energies" can be directly experienced (as Moses could see God's back and live). These Energies are considered to be uncreated in nature. The presence of the Energies is not to be taken as denial of the philosophical simplicity of God. Therefore, when speaking of God, it is acceptable within Eastern Orthodoxy to speak of His Energies as God. However, even taking this status into account, in some sense it is also true that there is a priority

The important theological and soteriological distinction remains that humans experience God through His Energies, not His actual Essence. Traditionally, the Energies have been experienced as light, such as the light of Mount Tabor that appeared at the Transfiguration. Orthodox tradition likewise holds that this light may be seen during prayer by particularly devout individuals, such as the saints. In addition, it is considered to be eschatological in that it is also considered to be the Light of the Age to Come.

Unlike qualities such as being the Eternal Source (the Father), the Eternally Begotten (the Son), or the Eternally Proceeding (the Holy Spirit), the Energies of God are not considered to be unique to a specific hypostasis of the Holy Trinity. Instead, they are common to all three.

This doctrine was given its most complete defense by Saint Gregory Palamas, against charges of heresy brought by Barlaam of Calabria.