The in the book of Hebrews, where we read: Let us run with patience the race that is set before us, looking unto Jesus, the author and the finisher of faith (Hebrews 12:1-2a). That is what Jesus has come to do—to bestow faith and make it grow. One version translates this as, The pioneer and perfecter of faith. This story tells us that we are in the hands of One who does not always answer our prayers the way we expect, but in doing so he lifts us to a higher awareness of who he is, of his authority and power in the world and in life. Our faith, as a result, becomes stronger, cleaner, and truer. We are enabled to exercise it at a far higher level. Jesus is the Author and Perfecter of our faith. That is the meaning of the sign that Jesus performed that day.
Tom Landry, the former coach of the Dallas Cowboys, once said that the job of a coach is to cause men to do what they don't want to do so that they can achieve what they really want. That is what Jesus does: he puts us through circumstances we do not want to go through; he makes us face things we do not like to face in order to achieve what we have wanted with all our hearts all along. To do so requires the strengthening of faith.