One cannot achieve anything great in life without strength or bala.
Jagat-bala, worldly strength includes bahu-bala, physical power; artha-bala, money power; buddhi-bala, power of the intellect. Dharma-bala, the power of dharma is manifested by righteousness of dharma. Yoga-bala, the strength that comes from yoga is very powerful as it is based on purity, selflessness and compassion. Samyama-balam, the power of self-control by inextricably linked dharana (concentration), dhyana (meditation) and samadhi (ecstasy) controls the senses and the mind to become stronger. This power is strongest when it is tapo-bala, power of tapasya. Atma-bala is the strength of the Atman. When one thinks of oneself as the infinite Atman, one`s strength and power will be infinite. This is mukti, which makes one fearless and the person becomes the Self of everything.
One may read the scriptures and understand them, but it is almost impossible to digest them or make them practical without spiritual strength. We can acquire spiritual strength or Atma-bala by practising dharma,yoga and samyama.
Dr.Mahesh Chandra Panda