It is to be noted that contrary to popular perception, Puranas were not authored by Sage Vyasa, as the Puranas were composed by some scholars at a later date.
Sage Vyasa preferred the name Vāsudeva to Krishna in his Jaya Samhita, the original version of Mahabharata, for the reason that Krishna indicates a quality of a person -black complexioned, rather the name. Vāsudeva indicates that he was the son of Vasudeva, a name.
Pāṇini (600 BCE) in his Aṣṭādhyāyī (Sanskrit Grammar Rules) mentioned about Vāsudeva as a divinity, but not as a Krishna - vāsudevārjunābhyāṃ vun (4.3.98).
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If we study the original version of Mahabharata, sans interpolations, we can find the following crucial narrations about Vāsudeva.
- Contrary to Bhagavata Purana, it was not mentioned in the Jayasamhita that Vāsudeva/Krishna was born in a prison. The confinement of Devaki and Vasudeva is detailed in the Harivamsa Parva, a subsequent addition to Jayasamhita and the Vishnu Purana.
- Vāsudeva (Krishna) was mentioned for the first time in Jaya Samhita, at the time Draupadi Swayamvara, along with his brother Balarama, as a fully grown up adult. In the subsequent chapters, it was mentioned that both Vāsudeva and Balarama touched the feet of Yudhisthira. This indicates that both Vāsudeva and Balarama are younger to Yudhisthira.
- When Yudhisthira asks for the opinion of Vāsudeva/Krishna about performing Rajasuya Yagna (Sabha Parva), the latter narrates as to what transpired between them and Jarasandha.
- Here, he never mentions about his birth, but states about the arrogance of Kamsa, which led to his killing by Vāsudeva/Krishna, as a grown up adult (but not as mere boy, as mentioned in Bhagavata purana) and consequent rivalry with Jarasandha.
- Mention of Vāsudeva/Krishna’s childhood adventures, as depicted in some chapters of the expanded/interpolated Mahabharata, ie., by Shishupala in Sabha Parva, Vidura in Udyoga Parva, etc, are later date additions, but are not from Original Jayasamhita.
- Vāsudeva/Krishna, received a Chakra from AGNI/VARUNA in Khandavana Dahana episode (Adi Parva). It is not Sudarshana chakra, a weapon of Vishnu.
- Sage Vyasa did not describe any miracles of Vāsudeva.
