Pratibhat the effulgent light, brilliant conception, intuitive knowledge, faculty of spiritual perception
sarvan all, everything
Through the faculty of spiritual perception, the yogi becomes the knower of all knowledge -- Vibhuti Pada.
A yogi can intuitively perceive anything and everything. By samyama on the radiant light, he becomes the knower of all knowledge. All knowledge is mirrored in a yogi.
In short, as day succeeds dawn, impulsive nature is transformed into intuitive thought, by which the yogi possesses universal knowledge. It is the conquest of nature.