As believers, when we find sin still operating in our lives we start to question whether God's grace is really at work. Like Abraham, we start to doubt the promises of God and try to make them happen in our own human effort. We measure our righteousness by how well we are able to manage our sin. Our righteousness is not determined by our performance, but by the justifying work of Christ on the cross. His grace is at work in our lives, sanctifying us. Our good works cannot add anything to the righteousness that we have in Jesus.