Answer
Kṛṣṇa consciousness is the fully blissful and enlightened state of devotional service. Therefore, this buddhi-yoga is actually nothing but bhakti-yoga.
The word buddhi specifically refers to intelligence. So why does Kṛṣṇa use the term buddhi-yoga instead of directly saying bhakti-yoga? Śrīla Prabhupāda explains that buddhi-yoga refers to the transcendental quality of the work we perform. It means engaging one’s intelligence in practical action performed in Kṛṣṇa consciousness for the pleasure of Kṛṣṇa.
When one works in buddhi-yoga, there is no separate endeavor required for liberation, because liberation is automatically included within buddhi-yoga itself.
Those who work in Kṛṣṇa consciousness are already liberated because they are situated on the transcendental platform. Their actions are no longer influenced by the three modes of material nature, and therefore they are free from material bondage. The characteristic influence of the material guṇas no longer acts upon them.
Thus, buddhi-yoga naturally means freedom from the influence of the guṇas — in other words, liberation itself.
Devotional service of the highest quality is performed not for one’s personal enjoyment, but solely for the pleasure of Kṛṣṇa. That selfless service attitude is the true meaning of buddhi-yoga.
