It is indeed significant that the passage of the Gospel today took place immediately after Jesus and His disciples had experienced the transfiguration. After having entered into the glorious presence of God, they now return to reality, where Jesus enters into an encounter not only with a demon, but also with the 'faithless generation'.
He upbraids the people and even His disciples for being hard-hearted and without understanding. Even the boy's father doubted the power of Jesus. But when Jesus tells him that faith does not put limits on the power of God he acknowledges his lack of faith and looks to Jesus for help. At this moment he stands in contrast to the disciples who displayed their lack of trust.
Often when we are confronted with difficult situations in our life we tend to lose faith in God. We want to do things on our own strength. Jesus reminds us that only through prayer will we be able to participate and share in His power and have a part in His work. But more than this, even at the most desperate moments when prayer and trust seem useless, He invites us to go one step further and pray like the boy's father, "I do believe! Help my unbelief".
Lord, all things are possible to those who believe in You.