Question
What is source for claim that Sruti is more important than Smriti ? That Itihasa/Purana can be discarded if they conflict with
Vedas?
Answer
The answer is no. There are five Vedas as follows:-
1: Rigveda
2: Atharvaveda
3: Samveda
4: Yajurveda
5: Itihaas and puranas
The Atharvaveda supports this claim.
Atharvaveda 11:7:24 says that god created puranas and itihasa.
Verses, and Songs, and magic hymns, Purāna, sacrificial text. All the celestial Gods whose home is heaven sprang from the Residue
Proofs for fifth Veda:
"Nârada said: 'I know the Rig-veda, Sir, the Yagur-veda, the Sâma-veda, as the fourth the Âtharvana, as the fifth the Itihâsa-purâna (the Bhârata); the Veda of the Vedas (grammar); the Pitrya (the rules for the sacrifices for the ancestors); the Râsi (the science of numbers); the Daiva (the science of portents); the Nidhi (the science of time); the Vâkovâkya (logic); the Ekâyana (ethics); the Deva-vidyâ (etymology); the Brahma-vidyâ (pronunciation, sikshâ, ceremonial, kalpa, prosody, khandas); the Bhûta-vidyâ (the science of demons); the Kshatra-vidyâ - Chandoyoga Upanishad 7:1:2.
"A name is the Rig-veda, Yagur-veda, Sâma-veda, and as the fourth the Âtharvana, as the fifth the Itihâsa-purâna, the Veda of the Vedas, the Pitrya, the Râsi, the Daiva, the Nidhi, the Vâkovâkya, the Ekâyana, the Deva-vidyâ, the Brahma-vidyâ, the Bhûta-vidyâ, the Kshatra-vidyâ, the Nakshatra-vidyâ, the Sarpa and Devagana-vidyâ. All these are a name only. Meditate on the name. - "Chandoyoga Upanishad 7: 1:4.
"As clouds of smoke proceed by themselves out of a lighted fire kindled with damp fuel, thus, verily, O Maitreyî, has been breathed forth from this great Being what we have as Rig-veda, Yagur-veda, Sama-veda, Atharvâṅgirasas, Itihâsa (legends), Purâna (cosmogonies), Vidyâ (knowledge), the Upanishads, Slokas (verses), Sûtras (prose rules), Anuvyâkhyânas (glosses), Vyâkhyânas (commentaries). From him alone all these were breathed forth. - "Brihadarankya Upanishad 2:4:10.
"In this way all the Vedas are manifested along with the kalpas,rahasyas, Brahmanas, Upanishads, Itihas, anvakhyatas and the puranas." - Gopatha Brahman purva 2:10.
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