Krishna can be known not by challenging but by submitting
One cannot challenge the authority of the Supreme and know Him also at the same time. He reserves the right of not being exposed to such a challenging spirit of an insignificant spark of the whole, a spark subjected to the control of illusory energy. The devotees are submissive, and therefore the transcendental knowledge descends from the Personality of Godhead to Brahma and from Brahma to his sons and disciples in succession. This process is helped by the Supersoul within such devotees. That is the perfect way of learning transcendental knowledge.