The world system and sin fight against us in our desire to obey God. (Romans 7:14-25 2:1-3) Tune-up: An adjustment made to improve working order or efficiency. Quiz: Do we need a tune-up of our spiritual health and walk? (Luke 2:52; Proverbs 3:7-8; Proverbs 4:20-22; 1 Tim 4:8)