The Bhagavad Gita is among the world's greatest works of sacred literature. It is a portion of the larger Sanskrit work, The Mahabharata which tells the story of the dynastic struggle between the Kaurava and Pandava princes, all members of an extended family. The Gita recounts a critical episode in that struggle in which he two dynasties are preparing to face one another in an epic battle. It recounts the dialogue between the Pandava prince Arjuna and his charioteer Krishna. Arjuna, seeing his family members -- on both sides -- arrayed for battle becomes paralyzed with grief and foreboding of the senseless carnage that is about to occur. Whereupon, Krishna excoriates him for his weakness. In the course of the dialogue, Krishna discusses three forms of yoga: jnana (wisdom), karma (action), and bhakti (devotion). His message is essentially that Arjuna duty is to perform the actions that are appropriate to his station as a warrior and that the death and suffering that is about to occur does not touch the true self or selves of the warriors. What is essential about us is eternal. The climax of the dialogue comes in the eleventh chapter when Krishna reveals himself to Arjuna as God. This chapter is, to me, the very highest expression of mystical monotheism ever set down in verse.
There are countless English translations of The Gita. The translation contained in this volume is by Edwin Arnold, the illustrious English journalist/orientalist. His most famous work is The Light of Asia, a biography of the Buddha. Originally published in 1885, Arnold's Gita is a fine example of Victorian poetry. It is perhaps not the most literal translation of the original Sanskrit Gita, but it's poetic sensibility makes for exhilarating reading.
There is much that is contradictory in The Gita. So much so, that an unguided reading can be quite confusing. Here is where Franklin Edgerton's introductory essay on The Gita, included in this volume, provides excellent help. Edgerton is at pains to explain that The Gita is first and foremost a poetical work and that the requirements of consistency that we expect from an academic treatise do not apply. Consequently, we read Krishna's praise of all three types of yoga, with only a general sense that karma yoga is thought by the author to be the highest form of yoga; however, this may only be due to the fact that Arjuna, the primary audience of the treatise, is a warrior who, as a warrior, is expected to act.
For Edgerton, The Gita offers us an opportunity to compare the virtues of all three types of yoga. Jnana yoga is the path to spiritual liberation that involves a thorough intellectual understanding of reality. It is usually practiced by those who retire into meditation and religious study. In contrast, karma yoga is the path to spiritual liberation that involves embracing an active role in the great unfolding of worldly affairs. There is, however, an important cautionary message in Krishna's advice. While jnana yoga fails -- for Arjuna -- to fulfill his proper role in life and lead to liberation, one can easily mis-tread the path of karma yoga by becoming to passionately involved in the results of action. Karma yoga requires that the actor perform his or her duty without regard to the results. One must act of the sake of the proper action and not for a practical end. Karma yoga, properly pursued, includes the kind of dispassion that is characteristic of the reclusive jnana yogi. There are passages in The Gita which also praise bhakti yoga which has become the predominate form of Hindu worship. It involves an unrestrained love and devotion to God, in this case Vishnu or Krishna as he is manifested in The Gita.
Anyone interested in the religious tradition(s) of India must, by all means, read and become familiar with The Bhagavad Gita. It is a short and easily finished work, replete with astonishingly poetic visions of God. It will be puzzling, however, to anyone not already quite familiar with the yogic traditions of India. Here is where Edgerton can provide excellent guidance.