The one Supreme Reality has been styled, by various names by the learned seers, they call One by many names. This concept of Sanatana Dharma (Hinduism) is not easy to digest. The teachings of Vedas and Upanishads are incomprehensible to most since the languages were obscure. To make common people understand the immortal and universals teachings in Hinduism, Puranas with Hindu stories of Gods were written by Hindu seers. These are not mere stories or figment of imagination but the universal teachings of Hinduism told through symbols. The symbolism is often missed by devotees and scholars.
After the Vedic age of Hinduism, we get the Puranic age where the great sage Vyasa wrote all the great Puranas in which were given the stories of Gods in which the truths of the Vedas were interwoven. The sages of the Puranas did this with such skill that people did not realize that they were actually living a Vedic life when the followed the exhortations of the Puranas.
The Puranic sages like Vyasa and Valmiki were as great as the Vedic rishis. It is only due to their compassion that we are able to comprehend the esoteric meaning of the Vedas.
The one God has become the many and we worship all the gods, not necessarily knowing the important fact that all these gods are only aspects of the One God. The concept of the one Absolute cannot easily be grasped by the mind of the human being because of the dichotomy created in the mind between man and the world and the world and God. Hence, Vyasa gave us Puranas with stories of Hindu gods and goddesses.
Hindu stories actually magnify and simplify the pithy statements of the Vedas and Upanishads. The Puranas elaborated on these statements in the form of stories and anecdotes. The vedic injunctions like restraint, patience, compassion, chastity and other dharmas were illustrated in the Puranas through the lives of the great and noble men and women. As a result of listening to these stories, people developed a desire to shape their own lives according to the dharmas which they portrayed.
Source – Excerpts from the chapter ‘The Puranas’ in the book ‘The Science Called Hinduism” by Vanamali – page 105 to 106