Srimad-Bhagavatam: Canto 3 - Chapter 1 - Verse 42

Sanskrit:

श्रीशुक उवाचस इत्थमापृष्टपुराणकल्प: कुरुप्रधानेन मुनिप्रधान: ।प्रवृद्धहर्षो भगवत्कथायां सञ्चोदितस्तं प्रहसन्निवाह ॥ ४२ ॥

ITRANS:

śrī-śuka uvācasa ittham āpṛṣṭa-purāṇa-kalpaḥkuru-pradhānena muni-pradhānaḥpravṛddha-harṣo bhagavat-kathāyāṁsañcoditas taṁ prahasann ivāha

Translation:

Śrī Śukadeva Gosvāmī said: Thus the chief of the sages, who was always enthusiastic about describing topics regarding the Personality of Godhead, began to narrate the descriptive explanation of the Purāṇas, being so infused by Vidura. He was very much enlivened by speaking on the transcendental activities of the Lord.

Purport:

Great learned sages like Maitreya Muni are always very enthusiastic about describing the transcendental activities of the Lord. Maitreya Muni, being thus invited by Vidura to speak, appeared to be smiling because he actually felt transcendental bliss.