Even a changed life for the Christian is not God leaving the believer alone to grow but as 2 Peter 3:18 calls for a growth in grace. Titus 2:11-14 shows that it is only by God's grace that Christians are brought out of the worldly system, taught to reject godliness and embrace holiness. Holiness and perseverance characterize the believer only by God's grace. A changed life is motivated by God's grace, it is driven by God's grace and it is a result of God's grace. The perseverance of the saints is not driven by anything but the grace of God. It is always the saving grace and not human effort that makes the Christian grow in holiness, grace and righteousness.
It is no wonder why salvation by grace through faith is an offensive doctrine because people wish to take credit for themselves. Many people today die in their sins all because their pride teaches them that they can save themselves. It requires humility before repentance, repentance of one's own sinfulness before repentance unto salvation. Without humility, no man will ever see the need to repent of their sins and receive Jesus Christ as their Lord and Savior.