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What is Theosis?

Theosis is union with God — the goal and purpose of Orthodox Christian life, expressed by St. Athanasius: 'God became man so that man might become god.'

What Does Theosis Mean?

  • Theosis means participation in the divine nature (2 Peter 1:4) — not becoming God by essence, but sharing in His energies.
  • Orthodox theology distinguishes between God's unknowable essence and His uncreated energies, through which He truly communicates Himself.
  • Theosis is not reserved for mystics; it is the vocation of every baptized Christian.
  • It begins in this life and is fulfilled in the age to come.

How Does Theosis Happen?

  • Through the sacraments — especially Baptism, Chrismation, and the Eucharist — the Holy Spirit unites us with Christ.
  • Through prayer, fasting, and repentance, we cooperate with God's grace (synergy).
  • Through the ascetic struggle, we subdue the passions so that God can dwell in us.
  • The Church, the sacraments, and the saints are all means of theosis.

Theosis and Western Theology

  • Western Christianity often frames salvation primarily in forensic or juridical terms (justification, satisfaction).
  • Orthodoxy frames salvation as ontological transformation — a real change in the person's nature and relationship with God.
  • Both traditions affirm that salvation is a gift of grace; Orthodoxy emphasizes that grace is God Himself, not a created substance.
What is Theosis? | Orthodox Christianity 101