In the Book of Mormon, Alma is clear full of amazing counsel. In chapter 32 he challenges us to arouse and awaken out Faith then compares faith as a seed. The process which it describes is clearly spelt out as S.E.E.D is verse 28. It will first "Swell within your breast", then "Enlarge my soul", "Enlighten my understanding", then become "Delicious". It is an easy symbol that we can remember the process that happens as we "grow" our Seed of Faith.
Faith just like a Seed needs to be fed. If we do not take care of it by watering it or feeding our faith it it slowly wither away.
Alma 32:38 "But if ye neglect the tree, and take no thought for its nourishment, behold it will not get any root; and when the heat of the sun cometh and scorcheth it, because it hath no root it withers away."
It is so important that we continue to feed out faith and grow our testimonies so that it will not wither away.