origins of it all

Hinduism has a long history, and many books considered holy. In brief Hinduism evolved on the Indian subcontinent. The Vedas were the first texts, originally transmitted around 1500 BC. This was followed by the Brahmans who wrote the Upanishads around 400 BC.  Around this point is when religious wondering was common, from that Siddhartha Gautama who became the first buddha started Buddhism. Hinduism continued on with the writing of the Tantras, and the Bhagavad Gita around 300 and 100 BC. Throughout this time yoga was evolving into a refined systematized practice. The yoga sutra of Patanjali, more likely written by a group than an individual were written around 150 BC. It codified yogic practices creating the ashtanga or the 8 limbed practice. Each branch building on the previous until the final goal of enlightenment is reached.

Though yoga is seen as a form of spirituality of it's own, or just a form of exercise by others in the fitness community. The original point of the yoga postures was to stretch and strengthen the body so that longer easier meditation sessions were possible. These postures are only the third of the eight limbs. The first two limbs are yama and niyama: a list of five practices of morality, and five personal obeservances. Then asana or physical practice, followed by pranayama or breath control. Pratyahara: control of the sense for the use of turning them inward away from external objects of attachment. Dharana which is concentration, this being a concentration when all your senses and energy are focused on one thing. Dhyana or devotion and meditation of the divine. Dhyana is focusing so purely on the divine that your mind takes on the same character of the divine. Dhyana causes samadhi or union with the divine, as the mind concentrates and takes on the shape of the divine it merges with the divine.

So it would seem that the final goal of Hinduism; yoga specifically, is to become closer to god. Eventually connecting to and becoming one with god. It would only make sense that devotional chanting and a life of devotion and surrender is ideal in helping to reach this goal.