In Śrīmad-Bhāgavatam it is stated that Kṛṣṇa, the Absolute Truth, the Personality of Godhead, transmitted transcendental knowledge into the heart of Brahmā. This, then, is one way knowledge is received—through the heart. Thus there are two processes by which one may receive knowledge: One depends directly upon the Supreme Personality of Godhead, who is situated as the Supersoul within the heart of all living entities, and the other depends upon the guru, or spiritual master, who is an expansion of Kṛṣṇa. Thus Kṛṣṇa transmits information both from within and from without. We simply have to receive it. If knowledge is received in this way, it doesn’t matter whether it is inconceivable or not.
In Śrīmad-Bhāgavatam there is a great deal of information given about the Vaikuṇṭha planetary systems, which are beyond the material universe. Similarly, a great deal of inconceivable information is given in the Caitanya-caritāmṛta. Any attempt to arrive at this information through experimental knowledge will fail. The knowledge simply has to be accepted. According to the Vedic method, śabda, or transcendental sound, is regarded as evidence. Sound is very important in Vedic understanding, for if it is pure it is accepted as authoritative. Even in the material world we accept a great deal of information sent thousands of miles by telephone or radio. In this way we also accept sound as evidence in our daily lives. Although we cannot see the informant, we accept his information as valid on the basis of sound. Sound vibration, then, is very important in the transmission of Vedic knowledge.