The oldest religion of the people of India is Hinduism. It is a religion which was not propounded by a single individual, but was evolved out of the developments spanning several millennia. It has the distinction that it has assimilated the unique features of all the ages through which it evolved. From the time of its appearance it has grown by adapting itself to its environment. Several works have come forth as an expression of its doctrines from the very beginning. But there is no single gospel for Hinduism as, say, the Bible is for Christianity. The Vedas, the Brahmanas, the Upanishads, the Puranas, the Ithihasas, all reflect the thought of Hindu religion.
"Viewpoints: Environmental Awareness: The Hindu Perspective,"
Journal of Hindu-Christian Studies:
Vol. 6, Article 12.
Available at: http://dx.doi.org/10.7825/2164-6279.1081