If you are a christian you make an assumption that you understand the gospel. We all think we understand the gospel, and sometimes dangerously that can lead people to think they need to move on from the gospel. But the rest of our lives is spent understanding, applying, re-understanding and reapplying the gospel to our lives.
Last night I was looking at Mark 2 as confrontation begins between Jesus and the Pharisees, often we write the Pharisees off but I think we tend to do so too quickly. But there big problem is that they codify holiness and can't, won't or don't know how to fit Jesus and the gospel of the kingdom he brings into their framework. Fascinatingly I think we have the same problem - though for us it is that we take our eyes off the gospel and focus instead on fence building.
A genuine desire to be holy means that we put up all sorts of fences to protect us from every sinning. Where we go, who we spend time with, what you can buy, what you can read, watch and so on - we put fences around everyone. Now the motive is good we want to live differently, we want to please God but we aren't applying the gospel to our lives just putting up fences. And as we do so we have taken our eyes off the gospel and fixed them on religion as a means of pleasing God.