Key Christian Terms · In Plain Words
Sanctification: Growing to Be Like Jesus
Sanctification means being set apart for God and then, day by day, being made more like Jesus by the Holy Spirit.
Justification is God’s verdict in a moment. Sanctification is the lifelong journey that follows: God patiently changing our hearts, habits and character until we reflect his Son.
“But we all, with open face beholding as in a glass the glory of the Lord, are changed into the same image from glory to glory, even as by the Spirit of the Lord.”
2 Corinthians 3:18 (KJV)
In Plain Words
What Does Sanctification Mean?
In one sentence
Sanctification means being set apart for God and then, day by day, being made more like Jesus by the Holy Spirit.
To sanctify means to make holy, or to set apart for God. When someone trusts Christ, God sets them apart as his own. Paul could write to a troubled church, “ye are washed, but ye are sanctified, but ye are justified in the name of the Lord Jesus, and by the Spirit of our God” (1 Corinthians 6:11).
Then the growing begins. God does not leave us as we are. Little by little the Spirit reshapes us: “we all, with open face beholding as in a glass the glory of the Lord, are changed into the same image from glory to glory, even as by the Spirit of the Lord” (2 Corinthians 3:18). It is slow, sometimes painful, and certain.
The word itself: The Greek word hagiasmos comes from hagios, holy, the same root as “saint.” In the New Testament every believer is called a saint: not a super-Christian, but someone set apart for God and being made holy.
Sanctification in Three Tenses
Set apart
The moment you trust Christ, God claims you as his own. In that sense you are already holy in his sight.
Growing
Day by day the Spirit works in you, and you work with him, putting off old ways and putting on new ones.
Made complete
One day the work will be finished. When Jesus appears, we will be like him.
An Everyday Picture
A Garden, Not a Light Switch
Some things change in an instant, like flipping a light switch. Others grow, like a garden. You plant, water and weed; the sun and rain do what you never could. Over seasons, a patch of bare soil becomes something beautiful.
Sanctification is a garden. God gives the life and the growth, and he asks us to tend it: to read his word, pray, turn from sin and stay close to Jesus. Jesus said, “I am the vine, ye are the branches: He that abideth in me, and I in him, the same bringeth forth much fruit: for without me ye can do nothing” (John 15:5).
Philippians 2:12–13
God’s Part and Our Part
Paul tells believers to work out their salvation, because God is at work in them. Here is how the two fit together.
What the Bible Says
Three Key Verses
1 Thessalonians 4:3
“For this is the will of God, even your sanctification, that ye should abstain from fornication.”
In plain words: God’s will for your life is clear: that you grow in holiness.
Philippians 1:6
“Being confident of this very thing, that he which hath begun a good work in you will perform it until the day of Jesus Christ.”
In plain words: God finishes what he starts. He will complete his work in you.
Romans 12:2
“And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what is that good, and acceptable, and perfect, will of God.”
In plain words: Change comes from the inside out, as God renews the way you think.
Clearing It Up
What It Is and What It Isn’t
A common mix-up
“Holiness is for super-Christians.”
Every believer is called to it. “As he which hath called you is holy, so be ye holy in all manner of conversation” (1 Peter 1:15).
A common mix-up
“If I’m really saved, I won’t struggle.”
Even Paul wrote, “For the good that I would I do not: but the evil which I would not, that I do” (Romans 7:19). Struggle against sin is a sign the Spirit is at work, not a sign he is absent.
A common mix-up
“It’s all up to me.”
Or, “It’s all up to God, so I can sit back.” The Bible says both work together: “work out your own salvation with fear and trembling. For it is God which worketh in you” (Philippians 2:12–13).
How It Connects
Sanctification and the Other Big Words
The Bible’s big words are not separate ideas. They are different angles on one story: what God has done for us in Jesus.
Justified once in God’s court; sanctified over a lifetime.
New birth is the start; sanctification is growing up.
The righteousness God gives grows into right living.
Grace saves us and also trains us to live godly lives.
Daily turning from sin is part of growing holy.
We grow by trusting and abiding in Jesus.
Living It Out
Putting It into Practice
1
Stay close to Jesus
Fruit grows on branches that stay connected (John 15:5). Build a simple daily habit of Bible reading and prayer.
2
Fill your mind with truth
“Thy word have I hid in mine heart, that I might not sin against thee” (Psalm 119:11). Memorize one verse this week.
3
Grow with others
Holiness is not a solo project. Join a small group or find a mature Christian to pray with and be honest with about struggles.
Questions
Quick Questions
What is the difference between justification and sanctification?
Justification is God’s verdict: you are declared right with him, once and completely. Sanctification is God’s work in you: you are being made holy, gradually, over a lifetime. Justification changes your standing; sanctification changes your character. Many Christians describe them as distinct but never separated: everyone God justifies, he also sanctifies (1 Corinthians 6:11).
Can a Christian become perfect in this life?
Christians answer this differently. Most traditions teach that believers grow but will not be sinless until they see Christ (1 John 1:8; Philippians 3:12). Some, especially in the Wesleyan tradition, teach that God can give “entire sanctification,” a heart wholly devoted to love for God, in this life, while still allowing for weakness and mistakes. All agree we should press on toward Christlikeness.
Why does growth feel so slow?
Because it is real. Fruit takes seasons, and God is often more patient with us than we are with ourselves. Paul himself said, “Not as though I had already attained, either were already perfect: but I follow after” (Philippians 3:12). Look back over months and years, not days, to see God’s work.
Does God use hard times to make us holy?
Yes. Hebrews says God disciplines his children “for our profit, that we might be partakers of his holiness,” and that afterward it “yieldeth the peaceable fruit of righteousness” (Hebrews 12:10–11). God does not waste our suffering.
Keep Reading
Continue Your Study
Read the key passages for yourself, then explore the Bible books and topics where sanctification comes up most.
Scripture quotations are from the King James Version (KJV), which is in the public domain. Verse links open at BibleGateway.