Sin has become the focus of Christianity, and overcoming sin has become the goal of most Christians. That's the opposite of what the Bible actually teaches. Our focus should be Jesus (Heb. 12:1-2), and our goal should be knowing Him (Phil. 3:7-10). Then holiness comes as a fruit of that relationship, not as a root that produces it.
We can't get rid of sin in our lives by fighting sin, anymore than we can get rid of the darkness in a room by trying to shovel out the darkness. We have to turn on the light. Darkness is the absence of light; likewise, sin is the absence of God's light in our lives. We cannot get rid of darkness without light, and we cannot overcome sin unless the life of Christ is released in us. The absence of darkness does not produce light, but light dispels darkness. The absence of sin does not produce fellowship with God, but rather, fellowship with God produces victory over sin.
To overcome sin, we have to first turn on the life of God, and His life flowing through us will drive out sin -- but this poses a problem. Most people believe that we can't have the life of God flowing through us until we get rid of the sin in our lives. That's not true! And that's what the Gospel is all about.