In the Bible, God is described as holy, and as followers of Jesus Christ we are called to be holy as well. 

1 Peter 1:13 says, “just as he who called you is holy, so be holy in all you do; for it is written: ‘Be holy, because I am holy.”

What does holiness mean? It means separating yourself from the unholy, sinful and worldly; it is choosing to be set apart for God. But how do we become holy? 

Holiness is a lifelong pursuit, and sanctification is the means by which we attain holiness.

Sanctification is allowing the Holy Spirit to do His work in us so that we may become more like Jesus Christ, in other words, to become holy. So in simple words, becoming holy is about allowing the Holy Spirit to change and transform us each day into the likeness of Jesus.

Holiness is not accomplished overnight. What God seeks is not perfection, but obedience and submission to His work in and through us. It is also important to remember that holiness cannot be achieved in our own strength — that becomes moralism. True holiness can only be found in Jesus Christ, through the Holy Spirit’s working, that we may be holy just as God our Father is.