Luke 7:9 & Matthew 17:20 - Enough faith?

Many Christians become very frustrated because they feel as though they don't have enough faith. Reading Matthew 17:20 is cold comfort - if we can't move mountains then we musn't have enough faith! But this interpretation fails to capture what Jesus was saying. Jesus uses the term "great faith" 3 times (Matthew 8:10, 15:8 and Luke 7:9) and in each of these verses He is referring to a non-Jew. In Luke 7:9, Jesus is describing the incredible nature and quality of the centurion's faith - He is so amazed at this man's faith that he turns to the crowd around him and announces that he has "not found such great faith even in Israel." Now, the Greek word translated "great" is never used in the New Testament to express a large quantity, but rather, a large degree (ie. quality not quantity). Again, in Matthew 17:20, Jesus is declaring that their faith is limited in quality not quantity. Indeed, Jesus declares in this same verse that faith "as small as a mustard seed" can move mountains - but Mark 4:31 states that the mustard seed is the smallest seed you plant! Therefore, it can't refer to the size or quantity of your faith. Rather, it paints a wonderful picture of how Christian faith develops and grows - although a mustard seed is small it eventually grows into a tree! Faith is not some kind of irrational leap into the dark - it is a reasoned response to the objective evidence of scripture and the subjective evidence of past experience. Faith starts out small and grows as our understanding of scripture increases and our experience of God expands. In regard to moving mountains, Jesus was making no such promise. In Matthew 21:21, Jesus makes it clear that this is only an example of what faith can do, when we ask God in prayer, believing that He will do what we ask and having no doubts because what we are asking is in-line with scripture and is based on our past experience of God.