The great sage Vyāsadeva, after compiling the Śrīmad-Bhāgavatam and revising it, taught it to his own son, Śrī Śukadeva Gosvāmī, who was already engaged in self-realization.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
स संहितां भागवतीं कृत्वानुक्रम्य चात्मजम् । शुकमध्यापयामास निवृत्तिनिरतं मुनिः
sa saṃhitāṃ bhāgavatīṃ kṛtvānukramya cātmajam | śukamadhyāpayāmāsa nivṛttinirataṃ muniḥ
SB 1.7.8