Mark 9:24 has one of the most genuine confessions I have ever read: “I believe, help my unbelief.” This cry for faith comes from a father whose son is assaulted and tormented by demon. The disciples can’t help. He is beginning to fear that no one can. Yet, he hopes. He hopes that Jesus can. So, in the face of his fears, he shouts out, “I believe, help my unbelief.”
Here is what James Edwards has to say about this in his commentary on Mark (p.280).
True faith is always aware how small and inadequate it is. The father becomes a believer not when he amasses a sufficient quantum of faith but when he risks everything on what little faith he has, when he yields his insufficiency to the true sufficiency of Jesus. . .True faith takes no confidence in itself, nor does it judge Jesus by the weakness of his followers. it looks to the More Powerful one (1:7) who stands in the place of God, whose authoritative word restores life from chaos. True faith is unconditional openness to God, a decision in the face of all to the contrary that Jesus is able.
Brothers and sisters, Jesus is more than able. He is compassionate. He will respond when we cry out to Him with even the weakest faith, I believe, help my unbelief.