In his original pristine state, the soul resides in the eternal spiritual world, where he enjoys an intimate relationship with God. Just as the intrinsic qualities of fire are heat and light and the intrinsic nature of water is liquidity, the soul’s eternal religion or nature (sanätana-dharma) is bhakti—pure devotional love and service to God. As the hand by nature serves the whole body, the jéva, who is constitutionally part of God, serves the complete whole. Sanätana-dharma is dissimilar to the Western concept of "religion," which indicates faith or belief that is potentially subject to change with time and circumstances; sanätana-dharma indicates the eternal, unchanging function of the eternal jéva in his eternal relationship with God.

Because bhakti (devotional service) cannot be forcibly imposed but must, rather, be a voluntary and natural expression of the soul, God endows the jéva with free will. By improper exercise of his minute free will, however, the soul may choose to ignore God’s predominance. So choosing, he is placed in the service of God’s own "inferior" or "external" energy (mäyä), which illusions the jéva, causing him to forget his eternal, spiritual identity as God’s servant. There are consequently two possible statuses for the soul—the "liberated" state (free from the influence of mäyä) and the "conditioned" state (illusioned by mäyä). Thus the jéva is the "marginal" energy of God, being subject, potentially, to both of God’s energies—matter and spirit.

When illusioned, the jéva descends to the material world. The world of matter is real, yet unreal. It exists, but its existence is temporal, although appearing substantial and permanent. Although the material energy (prakåti) is eternal, it assumes an infinite variety of temporary shapes and forms, which constitute merely a shadow of the reality of the spiritual world.

Entering the material world, the fallen jéva takes birth in a material body, which, under the influence of mäyä, he thinks to be his self. Thus embodied, the jéva, forgetful of his higher, spiritual identity, indulges his mind and bodily senses in temporary, material phenomena in an aimless pursuit of pleasure. The material world is a dramatic stage on which the illusioned jéva can act out, under the spell of mäyä, his artificial role as the puruña (enjoyer or predominator) of prakåti (material nature). In his original identity, the jéva is to serve and be "enjoyed" by God, but in his illusioned state he wants to act independently of God as the false lord of the material realm. Although he thinks himself independent of God, he is in actuality controlled by God through the agency of God’s "external" energy.

The material nature is divided into three "modes," or guëas (literally, "ropes"): sattva (goodness), rajas (passion) and tamas (ignorance). Acting individually or in various combinations, these guëas bind the soul to a particular mentality and course of worldly action. Under the law of karma, he enjoys or suffers the results of his actions. According to his actions and mental state, the law of karma awards him a new body after he leaves the present one. Although the soul is unborn and undying, upon leaving the body he is said to die, and upon entering a new one he is said to take birth. In this manner, entangled within a complicated network of actions and reactions, he transmigrates from body to body, experiencing the bitter and sweet fruits of his actions in an endless succession of rebirths. Thus imprisoned within saàsära, the wheel of repeated birth and death, the jéva perpetually suffers the miseries offered by his foreign, material existence.

After a long evolutionary ascent through the different species of plant and animal life, the soul finally enters a human form. By properly using the higher philosophical intelligence afforded by his human body, the bound jéva can analyze his existential position (as soul distinct from matter). With higher understanding of the self, he can extricate himself, by the discipline of yoga, from his bondage to the material world. Bhagavad-gétä teaches that to purify the materially contaminated consciousness is the goal of human life. In pure consciousness, the jéva acts in harmony with the will of God and is therefore happy. When, in the illusion of identifying with the material body, one acts in disharmony with the Supreme Will, one suffers the results of his sinful actions. The goal of yoga, therefore, is to liberate the jéva from his mistaken identification with the material body and the material world and to reconnect him to God (yoga literally means "link"). Yoga involves withdrawing the mind and senses from sense objects and, through unattached action, meditation, philosophical speculation or devotion (depending on which system of yoga one employs), gradually detaching oneself from the mundane world and ultimately realizing the self and his relationship with God.

Although there is some mention of añöäìga-yoga ("the eightfold path"), the Gétä deals primarily with three important systems of yoga: karma-yoga ("the yoga of action"), jïäna-yoga ("the yoga of knowledge") and bhakti-yoga ("the yoga of devotion"). In karma-yoga, one acts in selfless duty to the Supreme, sacrificing the fruits of one’s work to God. This purifies the actor and releases him from material entanglement. In jïäna-yoga, one gradually cultivates spiritual knowledge by philosophical induction, exercising the intellect to differentiate between matter and spirit. Bhagavad-gétä introduces these yoga systems not exactly as self-sufficient paths, but as a progressive "yoga ladder," the highest rung being bhakti-yoga. The paths of karma-yoga, jïäna-yoga and dhyäna-yoga are prescribed as the various preliminary aspects of a single way to approach God: bhakti, selfless devotional love.

In the Gétä, God possesses three principal features—Brahman, Paramätmä and Bhagavän. Brahman, the object of pantheistic philosophies, is the impersonal, all-pervasive aspect of God. Paramätmä ("Supersoul") is the localized form of God situated within the hearts of all embodied jévas, eternally accompanying them as the indwelling maintainer, witness, permitter and guide. Bhagavän is the complete form of God and is identified in the Gétä with Kåñëa Himself, the speaker of the Gétä. As such, Kåñëa is not the embodiment of any higher, abstract principle or force, but, as He repeatedly informs Arjuna, is Puruñottama, the "Supreme Person," the cause of all causes, the creator, maintainer and annihilator of the universe (although transcendental to it) and the supreme object of worship. He descends periodically, in His original spiritual form (or in the form of an avatära, or incarnation), to deliver the pious and to reestablish the principles of religion. The supreme principle of religion for the jéva is to surrender voluntarily unto Him and become His loving devotee.