And if God still works, how I regard and deal with sin is important.
Does someone celebrate his past sin? Does he remember how cool or fun some past "adventure"was? Do they hang onto "stuff" that leave them open to temptation? Do they expose themselves to opportunities for sin?
Sin and failures from the past are not small things. We build our presents and our futures from our pasts. But more important is how we make choices in the present and establish practices going into the future/ We can choose disciplines that strengthen current right practices or prepare us to make right decisions. For example, we can immerse our thinking in what God thinks. We can read, meditate or memorize the scripture. We can read biographies, commentaries or other books espousing kingdom values and ways. We can regularly and consistently spend time with other followers. And there is prayer in all its different expressions.
What is first ... how we set our hearts toward God and toward living a positive Christ-like life, and not being consumed by what we should not be doing.