"There is a famous verse from the Upanishads which says that you cannot reach Parama Purus´a unless you are strong and full of energy. The word bala means that spiritual force which functions in a jiiva [living being] base. In ordinary parlance, however, bala means “capacity”. It depends upon the extent to which one makes use of one’s physical, psychic and spiritual energy. A person may have immense capacity, but to the extent that he or she does not utilize it, it does not become helpful in God-realization. Bala, therefore, depends on the extent of the use of one’s capacity.
When the divine bridge was constructed by Rama to cross the ocean, Hanuman brought mountains, but the squirrel brought only small pebbles. Both were strong and full of energy, as each was working to his full capacity.
Thus even a comparatively weak person can become balava´n [strong] by utilizing the small energy he or she has. Whatever power, energy, you have, utilize it for sa´dhana´ and service, and you are balava´n, fit to reach Parama Purus´a. None of you need, therefore, despair. Each has the requisite wherewithal to reach the Almighty."
Shrii Shrii A'nandamu'rti
A’nanda Vacana’mrtam Part 23