The idea is that one cannot set his imperfect reason above the authority of the Vedas. The orders of the Vedas must be obeyed as they stand, without any mundane reasoning. The so-called followers of the Vedic injunctions make their own interpretations of the Vedic injunctions, and thus they establish different parties and sects of the Vedic religion. Lord Buddha directly denied the authority of the Vedas, and he established his own religion. Only for this reason, the Buddhist religion was not accepted by the strict followers of the Vedas. But those who are so-called followers of the Vedas are more harmful than the Buddhists. The Buddhists have the courage to deny the Vedas directly, but the so-called followers of the Vedas have no courage to deny the Vedas, although indirectly they disobey all the injunctions of the Vedas. Lord Caitanya condemned this.
The examples given by the Lord of the conchshell and the cow dung are very much appropriate in this connection. If one argues that since cow dung is pure, the stool of a learned brāhmaṇa is still more pure, his argument will not be accepted. Cow dung is accepted, and the stool of a highly posted brāhmaṇa is rejected. The Lord continued:
"The Vedic injunctions are self-authorized, and if some mundane creature adjusts the interpretations of the Vedas, he defies their authority. It is foolish to think of oneself as more intelligent than Śrīla Vyāsadeva. He has already expressed himself in his sūtras, and there is no need of help from personalities of lesser importance. His work, the Vedānta-sūtra, is as dazzling as the midday sun, and when someone tries to give his own interpretations on the self-effulgent sunlike Vedānta-sūtra, he attempts to cover this sun with the cloud of his imagination.
"The Vedas and Purāṇas are one and the same in purpose. They ascertain the Absolute Truth, which is greater than everything else. The Absolute Truth is ultimately realized as the Absolute Personality of Godhead with absolute controlling power. As such, the Absolute Personality of Godhead must be completely full of opulence, strength, fame, beauty, knowledge and renunciation. Yet the transcendental Personality of Godhead is astonishingly ascertained as impersonal.