Bhagavad Gita 18.68
य इदं परमं गुह्यं मद्भक्तेष्वभिधास्यति |
भक्तिं मयि परां कृत्वा मामेवैष्यत्यसंशय:
Translation
Amongst My devotees, those who teach this most confidential knowledge perform the greatest act of love. They will come to Me, without doubt.