One without knowledge does not obtain liberation even in a hundred births, no matter which religious faith he follows.

Sri Sankara, indicated in Bhaja Govindam says: - [Jnana Viheena Sarva Mathena Bajathi na Muktim janma Shatena] - One without knowledge does not obtain liberation even in a hundred births, no matter which religious faith he follows. 

Thus it proves he religion is not the means to self-realization .

When Upanishad itself declares:- sarvam khalvidam Brahma - all this (universe) is verily Brahman. By following back all of the relative appearances in the world, we eventually return to that from which it is all manifest – the non-dual reality [ Chandogya Upanishad]. 

Then it is no use going roundabout way, trace the Brahman which is the formless substance and the witness of the universe, which is in the form of mind. By tracing the source of the mind or universe one will be able to realize the Brahman. 

Thus, self-knowledge is meant only for those who have intense urge, and courage to accept the truth with humility and reject the untruth. Since people start comparing with their scriptural knowledge, it becomes impossible to assimilate and realize the non-dual truth. Therefore, there is no need to convince anyone other than our own-selves to get the firm conviction. 

Gaudapada says: - the merciful Veda teaches karma and upaasana to people of lower and middling intellect, while Jnana is taught to those of higher intellect.

So the Sages clearly indicate rituals and theories are not meant for those who are searching for the higher knowledge or wisdom. The path of wisdom is the only means. –FORMLESS PATH