Śrīmad-Bhāgavatam · Text 11.3.43
Who is speaking and story frame
श्रीआविर्होत्र उवाच
कर्माकर्मविकर्मेति वेदवादो न लौकिक: ।
वेदस्य चेश्वरात्मत्वात् तत्र मुह्यन्ति सूरय: ॥ ४३ ॥
śrī-āvirhotra uvāca
karmākarma vikarmeti
veda-vādo na laukikaḥ
vedasya ceśvarātmatvāt
tatra muhyanti sūrayaḥ
Śrī Āvirhotra replied: Prescribed duties, nonperformance of such duties, and forbidden activities are topics one can properly understand through authorized study of the Vedic literature. This difficult subject matter can never be understood by mundane speculation. The authorized Vedic literature is the sound incarnation of the Personality of Godhead Himself, and thus Vedic knowledge is perfect. Even the greatest learned scholars are bewildered in their attempts to understand the science of action if they neglect the authority of Vedic knowledge.
Read the purport on Vedabase.ioFrom Canto 10, chapter 14 onward, the translation and purports were completed by Śrīla Prabhupāda's disciples after his departure, and published by the Bhaktivedanta Book Trust.