By associating with the sages, Narada got the taste for hearing and chanting the glories of the Lord, and he developed a great desire for devotional service. Therefore, as described in the Vedanta-sutra, prakasas ca karmany abhyasat: if one is engaged simply in the acts of devotional service, everything is revealed to him automatically, and he can understand. This is called pratyaksa, directly perceived.

Srila Prabhupada; BG 9.2 purport