After the first sin, God promised that, no matter how bad things are, we still have a great advantage. We crush the devil's head, but he can only snap at our heels (Gn 3:15; Rm 16:20). No matter how defiled and dirty we become through sin, we are still called to be "holy and blameless in His sight" (Eph 1:4), "without stain or wrinkle or anything of that sort" (Eph 5:27). We can be "more than conquerors because of Him who has loved us" (Rm 8:37), for "nothing is impossible with God" (Lk 1:37).
However, we find God's glorious promises of victory difficult to believe. Often our everyday experiences are long losing streaks instead of an unstoppable string of victories. In a world of death, starvation, abortion, racism, war, divorce, alcoholism, broken families and exploitation, we see ourselves as losers, not winners. We are tempted to walk by the sight of our experiences rather than by faith in God's promises. We need encouragement.
Mary is a sign and glorious example of God's victory. She was undefeated (immaculate) from beginning to end (from conception to assumption). She was always on the winning team because she always let Jesus fight her battles. Look at Mary. Look what Jesus did for her. Believe and receive total victory in Christ.