I Thessalonians 4:3,4 “For this is the will of God, even your sanctification, that ye should abstain from fornication: That every one of you should know how to possess his vessel in sanctification and honour;”
After salvation, God’s desire for every believer is that they be sanctified. The Greek word behind this English word is the same one often translated “holy.” God wants you and I to be holy, which means separated for Him and His purposes. Things and places can also be “holy.”
Many churches and individuals have forsaken this doctrine (teaching) and live the way they want – just like the world. You cannot tell much difference between them and the unsaved they associate with. God says there ought to be a difference.
As the children of God, we ought to live above the world and its temptations. Although we will be tempted and will sometimes yield, living in sin should never become a way of life for the Christian.
The believer’s life and way are sanctified two ways. First, there is the Holy Spirit that dwells within us: “that the offering up of the Gentiles might be acceptable, being sanctified by the Holy Ghost” (Romans 15:16). Secondly, we are sanctified by the Word of God: “That he might sanctify and cleanse it with the washing of water by the word” (Ephesians 5:26). Jesus prayed: “Sanctify them through thy truth: thy word is truth” (John 17:17).
The Word of God cleanses us as we read it, believe it, and obey it. The Holy Spirit largely works through the Word. In God’s precious Book, we find “exceeding great and precious promises: that by these ye might be partakers of the divine nature, having escaped the corruption that is in the world through lust” (II Peter 1:4). This principle is also found in the Old Testament: “Thy word have I hid in mine heart, that I might not sin against thee” (Psalm 119:11).
Sanctification from sin begins at Calvary – the moment of salvation. It is a progressive process by God working in our hearts, to be finished when we are glorified. Because we are in Christ, we are sanctified, but in daily practice, we often have need for much growth.
It is God’s will that every believer be separate from the world and not adopt their sinful practices. We cannot identify with Christ and the world at the same time. We will serve one or the other – never both. God desires that we completely belong to Him: “Wherefore come out from among them, and be ye separate, saith the Lord, and touch not the unclean thing; and I will receive you” (II Corinthians 6:17).