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

Sanskrit:

जिज्ञासितं सुसम्पन्नमपि ते महदद्भ‍ुतम् ।कृतवान् भारतं यस्त्वं सर्वार्थपरिबृंहितम् ॥ ३ ॥

ITRANS:

jijñāsitaṁ susampannamapi te mahad-adbhutamkṛtavān bhārataṁ yas tvaṁsarvārtha-paribṛṁhitam

Translation:

Your inquiries were full and your studies were also well fulfilled, and there is no doubt that you have prepared a great and wonderful work, the Mahābhārata, which is full of all kinds of Vedic sequences elaborately explained.

Purport:

The despondency of Vyāsadeva was certainly not due to his lack of sufficient knowledge because as a student he had fully inquired about the Vedic literatures, as a result of which the Mahābhārata is compiled with full explanation of the Vedas.