What does it mean to be set apart for God? This lecture explores how the Holy Spirit shapes a believer’s life through Scripture, prayer, trials, and daily obedience.
Theme: The Work of God in Transforming the Believer into the Image of Jesus Christ
Key Scripture: 1 Thessalonians 4:3 (KJV)
"For this is the will of God, even your sanctification, that ye should abstain from fornication:"
In biblical theology, sanctification is the work of God by which a believer is set apart from sin, consecrated to God, and progressively transformed into the likeness of Jesus Christ through the power of the Holy Spirit.
The Greek word for sanctification, hagiasmos (ἁγιασμός), refers to holiness, consecration, or being set apart for God.
Sanctification involves both a new relationship with God and a transformed way of living.
It is important to distinguish three aspects of salvation:
Justification deals with our standing before God, while sanctification deals with our spiritual growth and daily conduct.
God does not save us merely to forgive our sins. He saves us to transform our lives.
1 Peter 1:15–16 (KJV)
"But as he which hath called you is holy, so be ye holy in all manner of conversation; Because it is written, Be ye holy; for I am holy."
The word conversation in this passage refers to one's conduct or manner of life.
God's holiness is the standard toward which believers are called to grow.
Hebrews 12:14 also declares:
"Follow peace with all men, and holiness, without which no man shall see the Lord:"
This does not mean that holiness earns salvation. Rather, holiness is a necessary characteristic of genuine salvation.
A person is not sanctified to become saved; a person who has been saved is sanctified.
Sanctification is therefore not optional in the Christian life.
An important biblical truth is that sanctification is fundamentally the work of God.
1 Thessalonians 5:23 (KJV)
"And the very God of peace sanctify you wholly; and I pray God your whole spirit and soul and body be preserved blameless unto the coming of our Lord Jesus Christ."
The believer cannot produce true holiness through human effort alone.
It is the Holy Spirit who transforms the heart, changes our desires, and enables obedience to God's Word.
2 Corinthians 3:18 (KJV)
"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."
Notice that the believer is being changed progressively.
The transformation is not instantaneous in every aspect of Christian conduct.
It is a lifelong process through which God increasingly conforms the believer to Christ.
Christian theology, particularly within the Reformed tradition, commonly identifies three aspects of sanctification.
This occurs when a person becomes united to Christ through salvation.
1 Corinthians 6:11 (KJV)
"And such were some of you: but 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."
Notice that Paul speaks of sanctification as something that has already occurred.
The believer has been set apart for God.
Acts 26:18 also speaks of those who are sanctified by faith in Christ.
This refers to the ongoing transformation of the believer throughout the Christian life.
Philippians 2:12–13 (KJV)
"Wherefore, my beloved, as ye have always obeyed, not as in my presence only, but now much more in my absence, work out your own salvation with fear and trembling. For it is God which worketh in you both to will and to do of his good pleasure."
The believer actively pursues holiness, but God is the One working within him.
Progressive sanctification involves:
This occurs when believers are completely freed from sin and made perfect in holiness.
1 John 3:2 (KJV)
"Beloved, now are we the sons of God, and it doth not yet appear what we shall be: but we know that, when he shall appear, we shall be like him; for we shall see him as he is."
This final transformation is closely connected with glorification.
The believer will no longer struggle against sinful desires because the work of sanctification will be complete.
Scripture identifies several means through which God accomplishes sanctification.
John 17:17 (KJV)
"Sanctify them through thy truth: thy word is truth."
The Holy Spirit uses the Scriptures to correct our thinking, expose sin, and guide us into righteousness.
A Christian who neglects God's Word neglects an essential means of spiritual growth.
Galatians 5:16 (KJV)
"This I say then, Walk in the Spirit, and ye shall not fulfil the lust of the flesh."
The Holy Spirit enables believers to resist sinful desires and develop godly character.
Galatians 5:22–23 describes the fruit of the Spirit, including love, joy, peace, longsuffering, gentleness, goodness, faith, meekness, and temperance.
These qualities provide evidence of the Spirit's transforming work.
Hebrews 12:10 (KJV)
"For they verily for a few days chastened us after their own pleasure; but he for our profit, that we might be partakers of his holiness."
God sometimes uses difficulties, correction, and trials to develop spiritual maturity.
James 1:2–4 teaches that the testing of our faith produces patience and maturity.
Prayer brings the believer into dependence upon God, while obedience demonstrates submission to His will.
Sanctification is not simply acquiring biblical knowledge; it involves putting that knowledge into practice.
Although sanctification is God's work, believers are commanded to actively pursue holiness.
Romans 6:12–13 (KJV)
"Let not sin therefore reign in your mortal body, that ye should obey it in the lusts thereof. Neither yield ye your members as instruments of unrighteousness unto sin: but yield yourselves unto God, as those that are alive from the dead, and your members as instruments of righteousness unto God."
Paul instructs believers not to allow sin to dominate their lives.
This teaches an important distinction:
God provides the power for sanctification, but believers are responsible for actively pursuing holiness through that power.
Christians must resist sin, put sinful behaviour to death, renew their minds, and pursue righteousness.
Romans 8:13 states:
"For if ye live after the flesh, ye shall die: but if ye through the Spirit do mortify the deeds of the body, ye shall live."
The word mortify means to put to death.
It refers to the deliberate rejection of sinful conduct through the power of the Holy Spirit.
One important theological question is whether a believer can achieve complete sinless perfection during this earthly life.
1 John 1:8 (KJV)
"If we say that we have no sin, we deceive ourselves, and the truth is not in us."
Even genuine believers continue to struggle with sin.
The Apostle Paul describes this conflict in Galatians 5:17, where the desires of the flesh oppose the desires of the Spirit.
However, there is a significant difference between struggling against sin and living comfortably under its dominion.
Romans 6:14 declares:
"For sin shall not have dominion over you: for ye are not under the law, but under grace."
In the Reformed understanding, the believer is progressively freed from the power of sin, even though the presence of sin remains until glorification.
Sanctification does not mean that the Christian never sins. It means that sin no longer holds the same ruling authority over the Christian's life.
Although justification and sanctification are closely connected, they must not be confused.
| Justification | Sanctification |
|---|---|
| A legal declaration by God | A transforming work of God |
| Occurs once upon justification | Continues throughout Christian life |
| Changes our standing before God | Changes our character and conduct |
| Based entirely on Christ's righteousness | Accomplished by the Holy Spirit through union with Christ |
| Complete at the moment of justification | Progressive until final perfection |
| Frees us from the condemnation of sin | Frees us progressively from the power of sin |
A critical theological principle is that sanctification is the consequence of justification, not the cause of it.
Good works do not make us justified. Rather, those whom God justifies are also brought into a life of sanctification.
The following passages provide biblical support for the doctrine of sanctification.
Leviticus 20:7 (KJV)
"Sanctify yourselves therefore, and be ye holy: for I am the LORD your God."
1 Peter 1:16 (KJV)
"Because it is written, Be ye holy; for I am holy."
Hebrews 12:14 (KJV)
"Follow peace with all men, and holiness, without which no man shall see the Lord:"
John 17:17 (KJV)
"Sanctify them through thy truth: thy word is truth."
2 Thessalonians 2:13 (KJV)
"But we are bound to give thanks alway to God for you, brethren beloved of the Lord, because God hath from the beginning chosen you to salvation through sanctification of the Spirit and belief of the truth:"
Galatians 5:16 (KJV)
"This I say then, Walk in the Spirit, and ye shall not fulfil the lust of the flesh."
Romans 12:2 (KJV)
"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."
2 Corinthians 3:18 (KJV)
"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."
Philippians 1:6 (KJV)
"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:"
Colossians 3:5 (KJV)
"Mortify therefore your members which are upon the earth; fornication, uncleanness, inordinate affection, evil concupiscence, and covetousness, which is idolatry:"
Romans 8:13 (KJV)
"For if ye live after the flesh, ye shall die: but if ye through the Spirit do mortify the deeds of the body, ye shall live."
2 Corinthians 7:1 (KJV)
"Having therefore these promises, dearly beloved, let us cleanse ourselves from all filthiness of the flesh and spirit, perfecting holiness in the fear of God."
1 Thessalonians 5:23–24 (KJV)
"And the very God of peace sanctify you wholly; and I pray God your whole spirit and soul and body be preserved blameless unto the coming of our Lord Jesus Christ. Faithful is he that calleth you, who also will do it."
1 John 3:2 (KJV)
"Beloved, now are we the sons of God, and it doth not yet appear what we shall be: but we know that, when he shall appear, we shall be like him; for we shall see him as he is."
| Biblical teaching | Principal scripture |
|---|---|
| God commands believers to pursue holiness | 1 Peter 1:15–16 |
| Sanctification is God's will | 1 Thessalonians 4:3 |
| Believers are set apart in Christ | 1 Corinthians 6:11 |
| Sanctification is accomplished by God | 1 Thessalonians 5:23 |
| The Holy Spirit transforms believers | 2 Corinthians 3:18 |
| God's Word sanctifies believers | John 17:17 |
| Believers must actively resist sin | Romans 8:13 |
| Spiritual growth is progressive | Philippians 2:12–13 |
| Genuine holiness produces godly fruit | Galatians 5:22–23 |
| Sanctification will ultimately be completed | 1 John 3:2 |
God does not merely save sinners from the penalty of sin; He also works within them to deliver them from sin's power.
Justification answers the question:
How can a sinful person be declared righteous before God?
Sanctification answers a different question:
How does a person who has been declared righteous progressively become more like Jesus Christ?
The answer is through the continuing work of the Holy Spirit, using the Word of God to transform the believer's thoughts, desires, attitudes, and conduct.
The goal of sanctification is not simply to make a Christian a better person. Its ultimate purpose is to conform the believer to the image of Jesus Christ.
Romans 8:29 (KJV)
"For whom he did foreknow, he also did predestinate to be conformed to the image of his Son, that he might be the firstborn among many brethren."
Justification delivers us from the penalty of sin. Sanctification progressively delivers us from the power of sin. Glorification will ultimately deliver us from the very presence of sin.
All three are aspects of God's saving work in Jesus Christ.
And as Philippians 1:6 reminds us, the God who begins the good work of salvation will bring it to completion.
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