What is Sanctification?

Defining Sanctification

The Bible uses the word “sanctification” in a few different ways. At its most basic definition, it means “to make holy” or “to set apart.” In the Old Testament, the priests and their instruments were sanctified (or “consecrated”) for their priestly ministry. Israel was to be Yahweh’s “holy nation,” set apart as his holy people.

When we come to the New Testament, we see that these words now describe Christians as his holy, set apart, and sanctified people. Yet, most frequently, they are referring to their growth in holiness, maturing as Christians in their faith. So, with such a wide variety of ways that the word “sanctify” is used, what does it truly mean for a Christian to be “sanctified”?

Types of Sanctification

Positional Sanctification

When speaking of how Christians are sanctified, it is best to understand it in two different yet complementary ways: positional and progressive.

Positional sanctification describes an aspect of our salvation that Christ has completed, alongside regeneration and justification, where he sets us apart and cleanses us by his blood.

In 1 Cor. 6:11, after giving a long list of sins, Paul says, “And such were some of you. But you were washed, you were sanctified, you were justified in the name of the Lord Jesus Christ and by the Spirit of our God.” The past tense of “sanctified” shows that it is a completed work. He has made us holy by cleansing us from our sin and setting us apart as his covenant people.

Progressive Sanctification

But, more frequently, Christians speak of progressive sanctification, which is the process by which Christians grow in holiness and Christlikeness—a process which is not yet complete, yet progresses over time.

First Thessalonians 5:23 says, “Now may the God of peace sanctify you completely,” which means that the sanctification process is currently incomplete (yet in a way that does not contradict the completed positional sanctification mentioned in 1 Cor. 6:11). What is incomplete is the Christian’s still struggle with sin. We still do not love the Lord with all our heart nor do we love our neighbors as ourselves. In a word, there is still a lot of unholiness in us, though we have been called to be holy by a holy God.

Paul touches on this truth in 1 Thessalonians 4:1-12 as well, and it is worth quoting it at length:

Finally, then, brothers, we ask and urge you in the Lord Jesus, that as you received from us how you ought to walk and to please God, just as you are doing, that you do so more and more. For you know what instructions we gave you through the Lord Jesus. For this is the will of God, your sanctification: that you abstain from sexual immorality; that each one of you know how to control his own body in holiness and honor, not in the passion of lust like the Gentiles who do not know God; that no one transgress and wrong his brother in this matter, because the Lord is an avenger in all these things, as we told you beforehand and solemnly warned you. For God has not called us for impurity, but in holiness. Therefore whoever disregards this, disregards not man but God, who gives his Holy Spirit to you. Now concerning brotherly love you have no need for anyone to write to you, for you yourselves have been taught by God to love one another, for that indeed is what you are doing to all the brothers throughout Macedonia. But we urge you, brothers, to do this more and more, and to aspire to live quietly, and to mind your own affairs, and to work with your hands, as we instructed you, so that you may walk properly before outsiders and be dependent on no one.

God’s Will for Sanctification

First off, it is important to see that it is God’s will for us to be sanctified. So many people wonder about what God’s will for their life is regarding their life circumstances (“Do I take this job or that job? Do I marry this person or that person?”) yet fail to see that the will of God is their sanctification, growing in the holiness to which he has called them.

The Ongoing Fight Against Sin

Be secondly, it is important to see that the Thessalonians, as holy as they may be, are not above being warned against sexual immorality and exhorted to continue to love each other. There is still a sanctifying fight against sin, to fight against the temptation of lust as well as the temptation of selfishness.

There will be cases when Christians lose the battle against sin and temptation, perhaps even backsliding into old patterns of sin. Yet despite backsliding, there will be an upward trend of holiness in the Christian’s life, as God conforms us to the image of his Son (Rom. 8:29).

The Agents of Sanctification

The Role of The Holy Spirit

But, in the case of progressive sanctification, who does the sanctifying? On the one hand, Paul was clearly exhorting the Thessalonians to put in their own effort to grow in holiness, to die to themselves, to put to death the lust of their flesh. Yet, on the other hand, in Romans 8:29, Paul says “For those whom [God] foreknew he also predestined to be conformed to the image of his Son”—a work that evidently belongs to God.

When it comes to our progressive sanctification, both God and the Chirstian are active. God is active in and through his Holy Spirit, which indwells the believer. The Holy Spirit, as his name would suggest, works to make believers holy, by convicting them of sin, empowering them to put sin to death (Rom. 8:13), and to bear the fruit of the Spirit (Gal. 5:22-23).

The Believer’s Role

The believer, therefore, is active in cooperating with the Spirit in his work and must put in effort to grow in holiness. It is possible to quench the Spirit (1 Thess. 5:19) and grieve the Spirit (Eph. 4:30) in his sanctifying work. Conversely, it is possible to walk by the Spirit, bear the fruit of the Spirit, and keep in step with the Spirit in such a way that we do not give in to the desires of our sinful flesh (see Gal. 5:16-26).

All of the commands in Scripture which exhort us to grow in our Christlikeness cannot be done apart from the Holy Spirit dwelling in us, nor will the Holy Spirit do the work for us. Yet, even if we quench and grieve the Spirit when we sin, the Spirit will still sanctify us by eventually waking us up to our sinful ways rather than depart from us.

Can Sanctification Be Complete in This Life?

Many people ask if this sanctification process will ever be complete, when we progress to complete holiness. Some theologians believe that it is possible to be fully sanctified in this life, however, I believe the Bible says otherwise. Paul is the perfect example. In Romans 7, he shows how he still struggled with sin, failing to do the good he wanted to do and doing the evil things he hated. In 2 Corinthians 12:7, he says that God gave him “a thorn in his flesh, a messenger of Satan” to keep him from become conceited. Paul saw that pride still lingered in himself; he was not too holy to become conceited.

The Hope Beyond This Life

As we grow in our sanctification, our sins may be less glaring to the outside world, but we see the sin lodged deep in our hearts with more clarity. Yet then we see the one who saved us from our sin more beautifully, and we rejoice in the fact that he could wash, sanctify, and justify such unholy wretches like us.