The Doctrine of Sanctification

If you go to church with any kind of frequency -- and certainly if you read the Bible -- you'll come across the terms "sanctify" and "sanctification" on a regular basis. These words are directly connected to our understanding of salvation, which makes them important. Unfortunately, we don't always have a solid grasp on what they mean.

For that reason, let's take a quick tour through the pages of Scripture to gain a deeper answer to this question: "What does the Bible say about sanctification?"

The Short Answer

At the most basic level, sanctification means "set apart for God." When something has been sanctified, it has been reserved for God's purposes alone - it has been made holy. In the Old Testament, specific objects and vessels were sanctified, set apart, for use in God's temple. In order for this to happen, the object or vessel would need to be ritually cleansed of all impurity.

The doctrine of sanctification has a deeper level when applied to human beings. People can be sanctified, which we usually refer to as "salvation" or "being saved." As with sanctified objects, people must be cleansed from their impurities in order to be made holy and set apart for God's purposes.

This is why sanctification is often connected with the doctrine of justification. When we experience salvation, we receive forgiveness for our sins and are declared righteous in God's eyes. Because we have been made pure, we are then able to be sanctified -- to be set apart for God's service.

Many people teach that justification happens in a moment -- what we understand as salvation -- and then sanctification is the lifelong process during which we become more and more like Jesus. As we'll see in the long answer below, this idea is partly true and partly false.

The Long Answer

As I mentioned earliest, it was common for specific objects and vessels to be sanctified for use in God's tabernacle or temple. The Ark of the Covenant is a famous example. It was set apart to such a degree that no person save the high priest was allowed to touch it directly under penalty of death. (Check out 2 Samuel 6:1-7 to see what happened when someone touched the sanctified Ark.)

But sanctification wasn't limited to temple objects in the Old Testament. Once, God sanctified Mount Sinai in order to meet with Moses and deliver the law to His people (see Exodus 19:9-13). God also sanctified the Sabbath as a holy day set apart for worship and rest (see Exodus 20:8-11).

Most importantly, God sanctified the entire Israelite community as His people, set apart from all other peoples of the world in order to accomplish His will:

You are to be holy to Me because I, Yahweh, am holy, and I have set you apart from the nations to be Mine.
Leviticus 20:26

It's important to see that sanctification is an important principle not only for the New Testament but throughout the entire Bible. Indeed, the New Testament authors often relied heavily on the Old Testament understanding of sanctification, as Paul did in these verses:

²⁰ Now in a large house there are not only gold and silver bowls, but also those of wood and clay, some for honorable use, some for dishonorable. ²¹ So if anyone purifies himself from anything dishonorable, he will be a special instrument, set apart, useful to the Master, prepared for every good work.
2 Timothy 2:20-21

As we move into the New Testament, however, we do see the concept of sanctification being used in a more nuanced way. This is largely because of everything that was accomplished through the death and resurrection of Jesus Christ.

Because of Christ's sacrifice, the door has been opened for all people to become justified -- to be forgiven of their sin and declared righteous before God. In the same way, the door has been opened for all people to become sanctified. Once we have been made pure by the blood of Jesus (justification), we qualify as worthy to be set apart for service to God (sanctification).

The question that modern scholars often wrestle with has to do with the timing of it all. Many Christians have taught that justification is an instant event -- it happens once and then is over -- while sanctification is a process that occurs throughout a person's lifetime. Such a definition doesn't fit with the Old Testament understanding of sanctification, however. If a bowl or chalice needed to be sanctified for use in God's temple, it was cleansed with blood and became sanctified for immediate use. It follows that the same would be true of us.

Indeed, there are many passages from the New Testament that point to sanctification as an instant process alongside justification. For example:

⁹ Don’t you know that the unrighteous will not inherit God’s kingdom? Do not be deceived: No sexually immoral people, idolaters, adulterers, or anyone practicing homosexuality, ¹⁰ no thieves, greedy people, drunkards, verbally abusive people, or swindlers will inherit God’s kingdom. ¹¹ And some of you used to be like this. 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.
1 Corinthians 6:9-11 (emphasis added)

By this will of God, we have been sanctified through the offering of the body of Jesus Christ once and for all.
Hebrews 10:10

On the other hand, there are another set of New Testament passages that seem to imply sanctification is a process, guided by the Holy Spirit, that occurs throughout a person's lifetime. For example:

I am sure of this, that He who started a good work in you will carry it on to completion until the day of Christ Jesus.
Philippians 1:6

How do we reconcile these ideas? It's actually not difficult. There is certainly a process that followers of Jesus experience throughout the course of their lives. The best way to label this process is "spiritual growth" -- the more we connect with Jesus and experience the transforming work of the Holy Spirit, the more we grow as Christians.

Growing with Christ

Many people have used the word "sanctification" or "being sanctified" to describe this process, but they are really talking about spiritual growth.

If you are a follower of Jesus, you are fully sanctified. You are set apart to serve Him as a member of His kingdom. That doesn't mean you're perfect, however; it doesn't mean you won't sin anymore. The fact that you have been sanctified simply means all of your sins have been forgiven through the blood of Jesus -- even those sins you haven't committed yet have already been cleansed.

And because you have been sanctified, or cleansed, through the blood of Christ, you now have the opportunity to experience spiritual growth through the power of the Holy Spirit. You can become more and more like Jesus.