On what basis are puranas named?
The Puranas are named according to following points (these are my observations):
- On the basis of which deity is glorified.
- On the basis of which Kalpa events are mentioned.
- On the basis of who is narrator of events.
- On the basis of to whom the events are being narrated.
The complete list of Puranas and why they are named so is given in Shiva Purana, Uma Sanhita, Chapter 44.
O Taṇḍi, Brahma the four-faced deity is the main speaker. Hence, O sage, the first Purāṇa is called Brāhma.
The second Purāṇa is called Padma. It is so called because it mentions the greatness of the Padmakalpa.
Another Purāṇa composed by Parāśara and enlightening the details of Viṣṇu is called Vaiṣṇava Purāṇa. It is said to be composed by Vyāsa since there is no difference between father and son.
Those who know the Purāṇas speak that purāṇa as Śiva Purāṇa wherein there are many stories of Śiva in its earlier and later forms.
Where the stories of the goddess Durgā are mentioned, it is said to be Bhāgavata Purāṇa as well as Devīpurāṇa.
130-131. The Purāṇa narrated by Nārada is called Nāradīya. The seventh Purāṇa is called, O Taṇḍi, Mārkaṇḍeya because the great sage Mārkaṇḍeya is the speaker therein. Since it is related to the fire-god, the Purāṇa is called Āgneya. Since it recounts future events the Purāṇa is called the Bhaviṣya Purāṇa.
- Since the transformation of Brahman is narrated the Purāṇa is called Brahmavaivarta. Since the story of Liṅga is mentioned it is called Liṅga Purāṇa.
133-135. O sage, the twelfth Purāṇa Varāha is so called because it contains the story of Varāha, the great Boar. In the Skanda Purāṇa the speaker is lord Śiva himself and the listener is Skanda. In the Vāmana Puraṇa the story of Vāmana (the Dwarf-god) is mentioned. The Kūrma Purāṇa contains the story of Kūrma (the tortoise-god). The Matsya Purāṇa is so called because it is expounded by Matsya. The Garuḍa Purāṇa is so called because the speaker is Garuḍa himself. Since the story of the entire cosmic egg is mentioned, the last Purāṇa is called Brahmāṇḍa Purāṇa.
But please note that there is some contradiction on Bhagavata Purana, as you can see Shiva Purana said it is Devi Bhagavata but in Vishnu Purana preface, section 5, it is said to be Shrimad Bhagavata Purana.
It is named Bhágavata from its being dedicated to the glorification of Bhagavat or Vishńu.
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