SB 11.3.43
sri-avirhotra uvaca
karmakarma vikarmeti
veda-vado na laukikah
vedasya cesvaratmatvat
tatra muhyanti surayah
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Sri Avirhotra 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.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Prescribed duties authorized by revealed scripture are called karma, whereas the failure to execute one’s highest duty is called akarma. The performance of forbidden activities is called vikarma. Thus karma, akarma and vikarma are established by the authorized explanations of Vedic literature. They cannot be ascertained merely through mundane exercises in logic. In the Srimad-Bhagavatam (6.16.51) the Lord says, sabda-brahma param brahma mamobhe sasvati tanu: “I am the form of the transcendental vibrations of the Vedas, such as omkara and Hare Krsna Hare Rama, and I am the Supreme Absolute Truth. These two forms of Mine — namely, the transcendental Vedic sound and the eternally blissful spiritual form of the Deity are My eternal forms; they are not material.” Similarly, it is stated in the Bhagavatam (6.1.40), vedo narayanah saksat svayambhur iti susruma: “The Vedas are directly the Supreme Personality of Godhead, Narayana, and are self-born. This we have heard from Yamaraja.” In the Purusa-sukta (Rg Veda, mandala 10, sukta 90, mantra 9) it is stated, tasmad yajñat sarva-huta rcah samani jajñire/ chandamsi jajñire tasmat: “From Him, Yajña, came all sacrificial offerings, hymns of invocation and songs of praise. All the mantras of the Vedas come from the Lord.” All the incarnations of the Supreme Personality of Godhead are completely transcendental and free from the four defects of conditional life, namely mistakes, illusion, cheating and imperfect senses. So Vedic knowledge, being a plenary manifestation of the Supreme Lord, is similarly infallible and transcendental.
Srila Bhaktisiddhanta Sarasvati Thakura has pointed out that in the material world, which is controlled by the illusory energy of the Lord, a particular sound vibration is discarded after describing its object. But on the spiritual platform called Vaikuntha nothing is ever lost, and thus sabda-brahma, or the Personality of Godhead in His form as transcendental sound, is eternal.
In ordinary human discourse one can ascertain the meaning of human words by understanding the intention of the speaker. But since Vedic knowledge is apauruseya, or transcendental, one can appreciate its purport only by hearing from the standard authorities in the chain of disciplic succession. This process is prescribed by the Lord Himself in Bhagavad-gita (evam parampara-praptam). Thus, even highly learned scholars who proudly neglect this simple descending process are certainly bewildered and embarrassed in their hopeless attempt to ascertain the ultimate meaning of Vedic knowledge. The four sons of Lord Brahma declined to answer the question of King Nimi since at that time the King was a mere child and therefore not capable of seriously surrendering to the process of hearing through disciplic succession. Srila Madhvacarya has pointed out in this regard, isvaratmatvad isvara-visayatvat. Because the Vedas describe the unlimited Personality of Godhead, Vedic knowledge cannot be approached by mundane methods of comprehension.