Bg 2.46

yāvān artha uda-pāne
sarvataḥ samplutodake
tāvān sarveṣu vedeṣu
brāhmaṇasya vijānataḥ
Synonyms: 
yāvān — all that; arthaḥ — is meant; uda-pāne — in a well of water; sarvataḥ — in all respects; sampluta-udake — in a great reservoir of water; tāvān — similarly; sarveṣu — in all; vedeṣu — Vedic literatures; brāhmaṇasya — of the man who knows the Supreme Brahman; vijānataḥ — who is in complete knowledge.
Translation: 
All purposes served by a small well can at once be served by a great reservoir of water. Similarly, all the purposes of the Vedas can be served to one who knows the purpose behind them.
Purport: 

The rituals and sacrifices mentioned in the karma-kāṇḍa division of the Vedic literature are meant to encourage gradual development of self-realization. And the purpose of self-realization is clearly stated in the Fifteenth Chapter of the Bhagavad-gītā (15.15): the purpose of studying the Vedas is to know Lord Kṛṣṇa, the primeval cause of everything. So, self-realization means understanding Kṛṣṇa and one’s eternal relationship with Him. The relationship of the living entities with Kṛṣṇa is also mentioned in the Fifteenth Chapter of Bhagavad-gītā (15.7). The living entities are parts and parcels of Kṛṣṇa; therefore, revival of Kṛṣṇa consciousness by the individual living entity is the highest perfectional stage of Vedic knowledge. This is confirmed in the Śrīmad-Bhāgavatam (3.33.7) as follows:

aho bata śva-paco ’to garīyān
yaj-jihvāgre vartate nāma tubhyam
tepus tapas te juhuvuḥ sasnur āryā
brahmānūcur nāma gṛṇanti ye te

“O my Lord, a person who is chanting Your holy name, although born of a low family like that of a caṇḍāla [dog-eater], is situated on the highest platform of self-realization. Such a person must have performed all kinds of penances and sacrifices according to Vedic rituals and studied the Vedic literatures many, many times after taking his bath in all the holy places of pilgrimage. Such a person is considered to be the best of the Āryan family.”

So one must be intelligent enough to understand the purpose of the Vedas, without being attached to the rituals only, and must not desire to be elevated to the heavenly kingdoms for a better quality of sense gratification. It is not possible for the common man in this age to follow all the rules and regulations of the Vedic rituals, nor is it possible to study all of the Vedānta and the Upaniṣads thoroughly. It requires much time, energy, knowledge and resources to execute the purposes of the Vedas. This is hardly possible in this age. The best purpose of Vedic culture is served, however, by chanting the holy name of the Lord, as recommended by Lord Caitanya, the deliverer of all fallen souls. When Lord Caitanya was asked by a great Vedic scholar, Prakāśānanda Sarasvatī, why He, the Lord, was chanting the holy name of the Lord like a sentimentalist instead of studying Vedānta philosophy, the Lord replied that His spiritual master had found Him to be a great fool and thus asked Him to chant the holy name of Lord Kṛṣṇa. He did so, and became ecstatic like a madman. In this Age of Kali, most of the population is foolish and not adequately educated to understand Vedānta philosophy; the best purpose of Vedānta philosophy is served by inoffensively chanting the holy name of the Lord. Vedānta is the last word in Vedic wisdom, and the author and knower of the Vedānta philosophy is Lord Kṛṣṇa; and the highest Vedāntist is the great soul who takes pleasure in chanting the holy name of the Lord. That is the ultimate purpose of all Vedic mysticism.