Sanctification

How believers would be thrilled if they but understood the Bible doctrine of sanctification!

Sanctification isn't a negative matter: "Don’t do this" and "Don’t do that." Rather, it's the positive truth that God wants us for Himself as a cherished possession, much like a bridegroom considers his bride his very own in a special and cherished way.

Bible sanctification is a twofold truth, affecting both our standing before God and our practical Christian walk while on this earth. 

In one sense every true believer in Christ has already been sanctified, or set aside to God, by the operation of the Holy Spirit.

…God chose you as the firstfruits to be saved, through sanctification by the Spirit and belief in the truth… (2 Thes 2: 13).

according to the foreknowledge of God the Father, in the sanctification of the Spirit… (1 Pet 1:2).

This has nothing to do with our conduct. God did it. Sanctification begins with Him. This is why Paul could write to even the sinful Corinthian believers and say: 

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 Cor. 6:11; cf. Acts 20:32; 26:18).  

In other words, God has set us apart for Himself.  This phase of sanctification — our standing before God — is based on the redemptive work of Christ in our behalf.

...we have been sanctified through the offering of the body of Jesus Christ once for all (Heb 10:10).

But now, in response to all He's done for us, God wants us to show our appreciation by conducting ourselves accordingly, setting ourselves apart ever more completely to Him. This is practical, progressive sanctification.

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 (1 Thes 4:3-5). 

This is the reason for Paul's benediction... 

Now may the God of peace himself sanctify you completely, and may your whole spirit and soul and body be kept blameless at the coming of our Lord Jesus Christ (1 Thes 5:23), 

...and why he said to Timothy:

Therefore, if anyone cleanses himself from what is dishonorable, he will be a vessel for honorable use, set apart as holy, useful to the master of the house,ready for every good work (2 Tim 2:21).

How can believers be more wholly set apart to God in their practical walk? By studying His Word!

Our Lord prayed, "Sanctify them in the truth; your word is truth" (Jn 17:17), 

and Paul declares that, "Christ loved the church and gave himself up for her, that he might sanctify her, having cleansed her by the washing of water with the word" (Eph 5:25-26).