Both the Mahābhārata and the Rāmāyaṇa, the two texts usually designated jointly as the Sanskrit Epics, are major sources for the history of religious and social ideas. Because their authors tend to present ideals and practices in a living situation, this material is potentially even more valuable, although the specific nature of the episodes raises greater difficulties and uncertainties in their interpretation. We must also guard against too readily reading into various terms their later technical meanings, even in the didactic parts of the Mahābhārata to which scholars most often refer. Moreover, a given word’s spread of meaning may well encompass both religious and more secular meanings; an excellent example of this is the term mantra, which not only designates the Vedic utterances used in connection with sacrifice and similar rituals but quite as frequently denotes the kind of consultation, counsel, or advice exchanged between kings and their counsellors (commonly mantrin). This issue is made all the more complex by the long period (perhaps fifth century BC to fourth century AD) over which both the Mahābhārata and the Rāmāyaṇa have reached their present form, during which both society and religion undoubtedly changed appreciably. This chapter discusses these developments.