But the path of the just is as the shining light, that shineth more and more unto the perfect day. Prov. 4:18.
Have you ever wondered why it is that the big sins seem to be overcome more easily than the "little" sins? The answer lies in the fact that we can overcome all sin so long as we are depending upon God's power, and that we cannot overcome any sin when we trust in our own power. But before we are willing to trust to God's power, we must come to the place of distrusting our own power. We find it easier to understand that we cannot overcome on the "big" sins, but much harder to understand that we are helpless to fight the devil ourselves in regard to the "little" ones. It is because we ourselves try to handle the areas of "little" sins that we are overcome.
Imagine yourself in a dark room, and you have become accustomed to the darkness. There is a closed Venetian blind at the window. If someone were to go to the cord at the side of the blind and yank it up all at once, the sudden sunlight would blind you. God, in His love, opens up the Venetian blind one slat at a time. He does not tell us all that He has to reveal to us at once. He begins with the big issues, the obvious sins. As we learn to trust Him on those, He goes on to the "little" sins.
If you approach a man on death row and talk to him about salvation, you don't begin by telling him to polish his shoes on Friday night. There is a sequence that God Himself recognizes. In Exodus 23 the Lord is talking about overcoming the enemy for His people. He promises to male all their enemies turn their backs. He says He will send hornets, which are extremely effective weapons! But then He adds, verses 29 and 30, "I will not drive them out from before thee in one year; lest the land become desolate, and the beast of the field multiply against thee. By little and little I will drive them out from before thee, until thou be increased, and inherit the land."
God knows that if He tried to change us all at once, and reveal to us every weakness that we have at one time, it would destroy us. So He takes it slowly, at a pace that we, in our weakness, can endure. But so long as we continue to seek fellowship with Him day by day, the work that He has started in our lives He will carry forward to completion (Phil. 1:6).