The sastras (scriptures) are not needed for an inward turned mind. They are meant for the rest.
(Bhagavan in ‘Talks with Sri Ramana Maharshi’, Talk 513)
Why is that ? All vedas, Gita etc come from inner experiences. So once you go within they are not needed
For those who do not go within, it gives them a verbal glimpse of something beautiful
For those who try to within it reminds them to stay on proper technique
For those who occasionally go within it gives various milestones. For exampleOh if you go within, truly, you will hear some enchanting music in your silence etc
For those who are within and perfected they interpret shastra perfectly for us. And now those Who cannot differentiate enlightened from unenlightened it serves as a simple method.
Bhavin