The contrast is, of course, the active nourishment of the tree. If they tend it with the understanding of its great value, it will continue to grow until it fulfills that great value.
Cross-Reference: Joseph’s faith was strengthened when he again took to his knees to ask God of his position.
Joseph Smith-History:29-30
29 In consequence of these things, I often felt condemned for my weakness and imperfections; when, on the evening of the above-mentioned twenty-first of September, after I had retired to my bed for the night, I betook myself to prayer and supplication to Almighty God for forgiveness of all my sins and follies, and also for a manifestation to me, that I might know of my state and standing before him; for I had full confidence in obtaining a divine manifestation, as I previously had one.
30 While I was thus in the act of calling upon God, I discovered a light appearing in my room, which continued to increase until the room was lighter than at noonday, when immediately a personage appeared at my bedside, standing in the air, for his feet did not touch the floor.
What Joseph did was once again act upon his faith. Once again, built upon the foundation of his earlier experience, Joseph again steps into the unknown. The exercise of faith was firm because he knew that he had been answered before, but this was a different question, a different purpose. Nevertheless, the continuation of the mission of the young man had been delayed, and now returned to a rapid track because he had taken action, because he had nurtured the incipient faith.