The next day, when they came down from the mountain, a large crowd met him. A man in the crowd called out, “Teacher, I beg you to look at my son, for he is my only child. A spirit seizes him and he suddenly screams; it throws him into convulsions so that he foams at the mouth. It scarcely ever leaves him and is destroying him. I begged your disciples to drive it out, but they could not.” “You unbelieving and perverse generation,” Jesus replied, “how long shall I stay with you and put up with you? Bring your son here.” Even while the boy was coming, the demon threw him to the ground in a convulsion. But Jesus rebuked the impure spirit, healed the boy and gave him back to his father. And they were all amazed at the greatness of God. Luke 9:37-43 NIV
It appears herein that Jesus is rebuking the man who asks for help for his son. Luke does not share some parts of the account which shed some light on who Jesus’ comment is directed toward.
In Mark 9:14 we learn that the teachers of the law were there arguing with the nine disciples who had not been on the mountain for the transfiguration. These were the nine disciples who were not able to extricate the demon from the possessed boy. And we see that these teachers of the law were arguing with the disciples.
I believe that Jesus’ comment was most likely directed at these teachers of the law, the generation of the day in general, and possibly somewhat at the disciples for their lack of faith in being able to drive out the demon and understanding His private messages to them.
We see that Jesus, rebuked the demon, cured the boy, and gave him back to his father. In doing so, I believe Jesus also helped the boy’s father, who had said to Jesus (seen in Matthew’s account) “I do believe; help my unbelief.” If we ask Jesus humbly to help us with our shortness of faith, He will do so. How He chooses to do this is all part of the wonderful plan of God. Jesus will never turn away one who sincerely comes to Him. Go to Jesus with all that is in you. Ask Him to help you. You shall receive help, the perfect help of God!!