Now the outer meaning of the riks can be understood from Sāyaņa’s commentary. But the secret sense, as stated earlier, is dependent on the meaning of the symbols. Yāska, the author of the nirukta, also says the meaning of the mantra is difficult to grasp. According to him the mantra called ‘brahman‘ revealed itself to the rişhis in tapas, askesis, not in any other way. He states: “It (mantra) brahman the self-born came to the rişhis who were doing tapas, therefore they became the rişhis, in that lies the rişhi hood of the rişhis” nirukta (2.11). Elsewhere he observes that the purport of the mantra is difficult to know. “The shore (of knowledge) of the mantra has to be reached by tapas” nirukta (13.13). It is clear that in the view of Yāska there is no other means except tapas to understand the meaning of the Veda and that mantra reveals itself to the rişhi stationed in tapas. What we have said in regarding the manifestation of the mantrās, its eternality and its being a creation – all these are decisively substantiated not only by the mantrās themselves, but justified by Yāska also.
The bŗhad devata supporting Yāska, says: “The mantra is not perceptible to one who is not a rişhi” BD (8.129). The treatment in the bŗhad devata of topics like the rişhi’s capacity for seeing, the purpose of the triad (the three types of mantrās), the efficacy of the rituals properly performed, goes without doubt to reinforce the position of the esoteric significance of the Veda. These are the dicta:
“He knows the Gods who knows the riks. They are to be approached through yoga with self-control and skill, understanding, general knowledge and above all tapasyā” BD (7. 130).
“The Gods accept the offering of the sacrificer who knows the Deity of the mantra but not of him who knows not the deity” (131).
“The Deity does not accept the libation offered in ignorance. Therefore the libation is to be offered to the Deity with self-control in the mind” (132).
“He is like a God worthy of praise in heaven even by the Gods, who is pure and studies the Veda with knowledge of the Gods and the mantra” (133).