Namaste Amrutji,

Till now I was satisfied with your answer but I feel you have deviated a little, so let me give the answer if you don't mind,

We ourselves cannot simply approach the Shastra directly, we require the Shastra to be unfolded to us by a Guru. Who is both realised and at the same time knows how to present the subject.

The Shastra will only become a Pramana through the teaching methodology adopted by the Guru. This teaching methodology helps us in bringing clarity about ourselves, that we are the whole.

How is this clarity brought in, it is done by the teaching methodology where Brahman's Svarupa Lakshana of Sat Chit and Ananda is explained, at this point we form an idea of Brahman as Sat Chit Ananda. This idea is called Brahma Kara Vritti. The unfolding of the Brahman is done in a 2 fold way one is Neti Neti, and the other is an investigation into the Svarupa Lakshana of Brahman. Once this is done the Brahman is unfolded to us in a crystal clear way as ourselves. At this point of time the Brahmakara Vritti disappears into the knowledge of Brahman.

The Guru with the help of the Shastra and the traditional teaching methodology imbibes the Brahmakara vritti into the student. This helps the student in realising the Brahman as his self.

For exemplars like Ramana Maharishi, Dattatreya and so on, the Brahmakara vritti is already present to them without any teaching and hence are ready to grasp the knowledge of "I am the whole".

But this Brahmakara Vritti is not easily formed for ordinary mortals hence we definitely require 1stly the Guru who knows both the Brahman as well as the way to present it.