One who has a little faith in Bhagavad-gita should learn Bhagavad-gita from a devotee, because in the beginning of the Fourth Chapter it is stated clearly that Bhagavad-gita can be understood only by devotees; no one else can perfectly understand the purpose of Bhagavad-gita. One should therefore learn Bhagavad-gita from a devotee of Krsna, not from mental speculators. This is a sign of faith. When one searches for a devotee and fortunately gets a devotee’s association one actually begins to study and understand Bhagavad-gita. By advancement in the association of the devotee one is placed in devotional service, and this service dispels all one’s misgivings about Krsna, or God, and Krsna’s activities, form, pastimes, name and other features. After these misgivings have been perfectly cleared away, one becomes fixed in one’s study. Then one relishes the study of Bhagavad-gita and attains the state of feeling always Krsna conscious. In the advanced stage, one falls completely in love with Krsna. This highest perfectional stage of life enables the devotee to be transferred to Krsna’s abode in the spiritual sky, Goloka Vrndavana, where the devotee becomes eternally happy.

Srila Prabhupada; Bg 8.28, ppt.