Spiritual progress begins the moment you can answer that question with a confident “YES.” There are three main reasons that people doubt their salvation:

1. Because they cannot remember the exact time or place. This is often because they were young and they wonder if they really understood or “did” what it takes to be saved.
2. Because of sin. Often in the midst of physical or financial difficulty, one begins to see sin in their lives and begin to wonder if they are really saved.
3. Because of ignorance to what salvation really is. Salvation in because of the finished work of Christ, and yet we often seek to find our assurance from our own works.

We could add a fourth to the list and that is, people doubt because they have not ever really been saved. They are professors, but not possessors! They are like Judas, they follow Christ but they have no faith in Christ. Moving on to maturity starts with the assurance of our salvation.