Means which imparts (conveys) true knowledge is called pramana. According to Shri Vallabhacharya:
Veda, Words of Shri Krshna (Gita),Bramhasutra of Vyas and Bhagwat together constitute a unified system conveying unanimous meaning. These four are complementary to each other and each one removes the doubts arising out of the previous one. E.g. the understanding of Gita and so on can clear any doubt in Veda. Any other means of knowledge which is in agreement with this system is also a pramana and never otherwise.
And thus Shri Vallabhacharyaji proclaimed:
“Ekam Shastram Devkiputra Gitam”
There is one Shastra i.e. the one sung by Shri Krshna and also explains in his Tatvarthadipnibandha Shastrarthprakaran that
Similarly on the same line he says:
Sarvesham Vedvakyanam Bhagwadachsaamapi Shroutoartho Hyamev.. Atra Sarvesham Pramananaam Ekvaavrthimaah Sarveshamiti.
All the Pramanas, Vedas and Words of Lord convey a unanimous meaning.
He also says:
“Arthoymev Nirivbhairapi Vedvakye Ramayanaha Sahitbharatpachairatrehe”
Anyeshch Shastravachaneihi Sahatatvasutre Nirnitayte Sahyayam Harina Sachev |
This is the meaning of all the Veda sentences, of Ramayana and of Mahabharata with Pancharatra of all other Shastravachans with Bramhasutra and thus he declares:
Krushnavakyanusaren Shastrarth Ye Vadanti hi |
Te hi Bhagwataha Prokta Suddhaste Bramhavadinaha |
Only those who speak the meaning of Vedas (Shastras) in accordance with “Krushnavakya” are true Bhagwats.