Part of growing in Christ is seeing changes in one’s life. 2 Corinthians 5:17 says that when a person turns to Christ in repentance and faith he becomes a new creation. The Holy Spirit indwells that person and provides him or her the power to change.
Before turning to Christ, a person is enslaved by sin. But at the moment of salvation, the Holy Spirit regenerates that person’s spirit and is made alive in Christ. The Holy Spirit makes the changes for the better possible.
One may be struggling with alcoholism, drug addiction, abuse of substances like humidors, no sense of purpose in life, no peace; but once that person turns away from sin and turns to God, he or she is changed from the inside and the change will eventually manifest outside. The person is changed from glory to glory because of the work of the Holy Spirit in that person’s life.