Legalism tempts us to rely on our own strength as the source of our salvation, even if it is the strength of our faith. As Christians, we know that we are justified by faith alone. But that does not mean that faith is what justifies us. Instead, God justifies us through faith in Christ. This is an important distinction. Even as we champion faith, we might easily start to rely on the intensity of our faith instead of the object of our faith. If we trust in the intensity of our faith, we are really trusting in ourselves. But saving faith looks away from self to Christ, and he alone has the power to save us.
In Mark 9:14–29, a desperate father comes to Jesus seeking healing for his son. The man’s son was possessed by an unclean spirit that made him mute, and often threw him into harm’s way (9:17–18, 22). In desperation, the father cries out to Jesus for help. Jesus tells him, “All things are possible for the one who believes” (9:23b). The father immediately recognizes the inadequacy of his own faith and cries out in verse 24:
“I believe, help my unbelief!”
His simple answer captures the essence of saving faith. The man’s faith is not in himself or even in the strength of his faith because he knows his faith is weak. He knows that his level of belief is not worthy of Christ, but he is looking to Jesus for help.
In his book, The King’s Cross, Tim Keller writes the following concerning the response of this father:
Jesus could have told the man, “I am the glory of God in human form. Purify your heart, confess all your sins, get rid of all your doubts and your double-mindedness. Once you have surrendered to me totally and can come before me with a pure heart, then you can ask for the healing you need.” But Jesus doesn’t say that—not at all. The boy’s father says, “I’m not faithful, I am riddled with doubts, and I cannot muster the strength necessary to meet my moral and spiritual challenges. But help me.” That’s saving faith—faith in Jesus instead of in oneself. Perfect righteousness is impossible for us, and if you wait for that, you will never come into the presence of God. You must admit that you are not righteous, and that you need help. When you can say that, you are approaching God to worship. (Page 121).
Keller is exactly right. We are not saved by the intensity of our faith, we are saved by faith’s object, namely Christ himself. Consider the following illustration from a sermon I preached on Mark 9:14–29 in 2016.
Imagine three men stuck on a cliff. They need to get to the edge of another cliff about 50 feet away. Nothing connects the two cliffs except for a single tightrope stretching the distance. They could try to walk the tightrope, but one slip and they would fall 300 feet onto jagged rocks. Thankfully for these men, a fourth person appears on the other cliff. He swiftly walks across the tightrope to come to their rescue. He is a master tightrope walker, and he is their rescuer. The rescuer tells the men that he can carry them one-by-one across the tightrope to safety. The first man has too much pride to listen. He says he will attempt to cross the rope on his own. About 5 steps in he slips and falls to his death. The second man gladly accepts the rescuer’s offer. He has full confidence in the rescuer’s ability to carry him to safety. He hops on the rescuer’s shoulders and enjoys every second of the ride. He has unflinching faith in his rescuer and he loves every second of the journey across the rope. They both arrive safely to the other side. The rescuer goes back for the third man, but this man is nervous. He believes in the rescuer’s ability to save him, but his faith is weak. He climbs on the rescuer’s shoulders trembling and sweating profusely. As the rescuer walks across the rope, the man screams in terror and nearly faints. But he holds on with all of his might to the rescuer. They make it to the other side safe and sound.
So who was saved? The second and the third man. What was the difference between them? One of them had strong faith; the other had weak faith, but they both arrived safely on the other side. Why? Because the object of their faith was the same. Their faith (strong or weak) was in the rescuer and he had the power to save.
Thanks be to God that we are not saved by the intensity of our faith, but by the object of our faith. So we say with full assurance, “Lord we believe, help our unbelief.”