These three words describe how salvation actually works in your life. Not how you got saved once at a youth rally, but how God is healing and transforming you right now into the person you were always meant to be.
Purification, illumination, and theosis aren’t three boxes you check off. They’re one continuous movement toward union with God. Think of them as overlapping stages in a lifelong process that starts at baptism and continues until you’re glorified at the resurrection.
Purification: Getting the Junk Out
Purification (the Greek word is katharsis) is about repentance. Real repentance, not just feeling bad about sin. It’s the hard work of rooting out disordered passions, anger, lust, greed, pride, all the stuff that keeps you from seeing God clearly.
This happens through confession, fasting, prayer, and keeping the commandments. When you’re battling habitual anger and you start confessing it regularly, fasting on Wednesdays, praying the Jesus Prayer when you feel rage rising, you’re doing the work of purification. You’re clearing out the obstacles between you and God.
It’s not about earning anything. You can’t purify yourself into heaven. But God won’t force healing on you either. Purification is cooperating with grace, letting the Holy Spirit do surgery on your soul.
Illumination: Learning to See
Illumination (photismos in Greek) is what happens when your spiritual eyes start working. Your prayer life gets clearer. You begin to perceive God’s presence in ways you couldn’t before. The Scriptures open up. You develop discernment.
Some of the Fathers talk about experiencing the uncreated light of God in prayer, not a metaphor, but an actual encounter with divine energy. Most of us won’t have visions. But illumination still happens when you move from distracted, mechanical prayer to sustained attention, when you start seeing Christ in your neighbor, when theological truth becomes lived reality instead of abstract doctrine.
This is why we say the pure in heart will see God. Purification prepares you for illumination. The more you clear out the passions, the more your spiritual vision sharpens.
Theosis: Becoming Like God
Theosis means deification. It’s the goal of everything. St. Athanasius put it bluntly: “God became man so that man might become god.” Not that we become divine by nature, that’s impossible. But we become divine by grace, participating in God’s own life and energy.
St. Peter writes that we become “partakers of the divine nature” (2 Peter 1:4). That’s not poetry. It’s what’s actually happening when you receive the Eucharist, when you pray, when you live in Christ through the Church. You’re being soaked in divine life, transformed from glory to glory.
Theosis shows up practically in love. A person far along in theosis looks like Christ, patient, self-sacrificing, joyful even in suffering. Think of the saints you’ve read about. Their lives radiate something different because they’ve been united to God so deeply that his character has become theirs.
Why This Matters for Converts
If you grew up Baptist or non-denominational here in Southeast Texas, this probably sounds strange. You’re used to salvation as a one-time decision, maybe at vacation Bible school or after a sermon at First Baptist. You asked Jesus into your heart and that was that.
Orthodoxy doesn’t deny that something real happens when you turn to Christ. But we’re talking about something bigger. Salvation isn’t a legal transaction where God declares you righteous and you’re done. It’s a healing process, a transformation, a marriage. You don’t get married and then ignore your spouse for fifty years. You grow together, become one flesh, learn to love.
That’s theosis. It’s why we keep coming back to confession, why we fast, why we show up for Liturgy every Sunday even when we’re tired. These aren’t religious hoops to jump through. They’re the means by which God actually changes us, purifies us, illumines us, unites us to himself.
The Long Haul
Here’s the hard truth: this takes your whole life. You’ll be working on purification until you die. You’ll have moments of illumination and then fall back into darkness. Theosis is the goal, but it’s not something you achieve and then coast.
That’s okay. God isn’t in a hurry. The Church has been doing this for two thousand years, and she knows the path. Come to confession. Fast when you can (and when you can’t, talk to your priest about what’s realistic with your refinery schedule). Pray the Jesus Prayer in your truck on the way to work. Receive the Eucharist. Let the process unfold.
Metropolitan Kallistos Ware has written beautifully about this, and Fr. Thomas Hopko’s talks on Ancient Faith Radio go deep into the practical side of the spiritual life. But honestly, the best way to understand purification, illumination, and theosis is to live it. Start showing up. Start confessing. Start praying. The rest will follow.
