I am not denying that there are remarkable consequences of belonging to Christ. We are indeed liberated from the bondage as well as the guilt of our sin. As Christians we have heard amazing cases of radical conversion and transformation. However, similar accounts can be found in every religion and even in secular programs. Transformed lives certainly witness to the power of the gospel, but precisely because the gospel itself is not our imperfect transformation but Christ's perfect work on our behalf.
Furthermore, Christians continue to fall short of God's glory - even in their best moments. Christ's saving ministry is sufficient even to save Peter, who denied Christ three times in the early morning hours of Good Friday. It is enough to save a believer whose marriage crumbles or who has fallen into serious immorality, as much as those who have destroyed someone's reputation through gossip, mistreated and employee, robbed an employer, or turned away from a friend in a time of crisis. No less in the middle and at the end than at the beginning, the believer clings to Christ's righteousness as the only appropriate attire in the presence of a holy God. The gospel is not about us or what we do, feel, experience, or think is important. It affects us at all of these levels, in varying degrees at various times, but the gospel is always an announcement concerning unrepeatable, unique, and unalterable facts. It is an objective announcement about that which God has done for us in his Son.
Source: Michael Horton, The Gospel-Driven Life: Being Good News People in a Bad News World, p. 70