Bhagwad Gita
Chapter 18, Verse 68
य इमं परमं गुह्यं मद्भक्तेष्वभिधास्यति।भक्ितं मयि परां कृत्वा मामेवैष्यत्यसंशयः।।18.68।।
For one who explains the supreme secret to the devotees, devotional service is guaranteed, and at the end he will come back to Me.