Jesus uses the parable about the mustard seed to show how great things can come from small beginnings. The mustard seed as a symbol of conversion. A little seed is planted in the heart and soul of an individual who nourishes it with prayer and study, and faith grows. Just as a plant does not grow quickly or bear fruit overnight, so our faith grows equally slowly. We need to be patient with our conversion and let it unfold as God would have it do.