Bhagavad Gita 18.68

य इमं परमं गुह्यं मद्भक्तेष्वभिधास्यति।भक्ितं मयि परां कृत्वा मामेवैष्यत्यसंशयः ॥१८.६८॥

ya imaṃ paramaṃ guhyaṃ madbhakteṣvabhidhāsyatibhakitaṃ mayi parāṃ kṛtvā māmevaiṣyatyasaṃśayaḥ

He who, with supreme devotion to Me, teaches this supreme secret to My devotees, shall undoubtedly come to Me.

गीता