The real you, the spirit man on the inside has been sanctified in Christ. The word sanctified means to be set apart and dedicated unto God. Sanctification of our spirit man was God’s part, now we respond by consecration of our soul and bodies. Jesus in praying for His disciples said in John 17 that we would be in the world but not of the world. In His prayer He prayed we would be sanctified by God’s truth, for His Word is truth.
Once born again we don’t have to live the way of the world. We can live a life set apart from fear, worry, doubt, sin, sickness, etc. All these things are in the world and are true, but there is Truth that reveals we have been set apart from all of that, God’s Word. If we will learn from the Word who we now are in Christ and become doers of the Word and not just hearers only, we will be set apart by the Truth. Become one with the Word of God by hearing and doing the Truth and you will live a sanctified life, set apart from the world.