When I was making a garden with my father-in-law, there were days when we would pray for rain, because we knew that if our plants went without it for any period of time they would wither and die. The ground needed a good drink to replenish itself, but our plants could sustain themselves between the rains if they received a heavy dew. This is true of our spiritual growth as well. We need regular rains to replenish the spiritual soil in which our souls grow strong, and thrive, but if we gather nightly dew we can sustain ourselves until the rains fall on us again... until the Holy Spirit falls full upon us and glorifies the Lord.