Joy is exemplified by a group of friends playing, or a carefree young girl singing to herself while engaged in her work. The happiness is rising from within and spreading out into the world!
Joy comes into the world through gentle means, but springs from a solid sense of self. The power of joy should never be underestimated. The enjoyment of learning and discovery, for example, has served as the source of much progress. Likewise, that which brings joy into the world is a source of considerable power.
If happiness is supported by personal stability, it will wear down the stiffest barrier and win over the hardest heart. True joy is a beacon in the world, and being so rare, its presence is an indication of great good fortune, both now and in the future. How could it be otherwise?