Some Christians face moments of crisis that strike at the very core of their faith. Perhaps it is an old sin that resurfaces or a recurring trial. It may be parenting a terminally ill or spiritually lost child.
In Mark 9:14–29, we read of a man who struggled deeply with the condition of his son. He brought this demon-possessed, self-destructive child to the disciples for healing. They were unable to help him. When the Lord Jesus finally comes to the man’s aid, He says, “All things are possible for one who believes.” The father’s tearful response is, “Lord, I believe; help my unbelief.”
How can this be? Can believers come to Christ and yet struggle with unbelief? John Calvin was realistic about the weakness of many believers’ faith. In his commentary on Mark 9, he states about the father’s mixed confession:
These two statements may appear to contradict each other, but there is none of us that does not experience both of them. . . . As our faith is never perfect, it follows that we are partly unbelievers; but God forgives us, and exercises such forbearance towards us, as to reckon us believers on account of a small portion of faith. It is our duty, in the meantime, carefully to shake off the remains of infidelity that adhere to us.
For a bold Reformer and a man who faced persecution, this may seem like an odd confession to some. Are believers partly unbelievers? Indeed, this reality of weak faith and unbelief is evident throughout the Bible. Abraham is called the father of the faith, and yet a lack of trust in the Lord was at the root of his cowardice and lying (Gen. 20:11). Moses could not believe that the Lord would make him a great deliverer (Ex. 4:11). Peter began to sink under the waves due to little faith and doubt (Matt. 14:31).
Especially during trials, Christians may still struggle with evil thoughts, moments of cowardice, or doubts about the Savior Himself. We must admit that these are indeed dangerous moments. When such thoughts are entertained, they must be repented of quickly. The answer, however, is not to remain in doubt or to be paralyzed with guilt. It is to come to Christ and to trust that His grace is sufficient to cover even your sins of unbelief. It is to know that even Christ’s own unwavering trust is a part of our gospel hope (Heb. 1:13).
If doubts or unbelief rise within you, take Calvin’s advice: shake off such thoughts; fight against them. But do not despair. On that difficult day, the father of the demon-possessed boy had his prayers answered. The demon was cast out, and the boy was restored, even after a final trial where it appeared that he had died (Mark 9:26). Despite our weaknesses and sins, remember, Jesus Christ is merciful and mighty to save.