Yato vā imāni bhūtāni jāyante yena jātāni jīvanti yat prayanti abhisaṃviśanti Tadvijijñāsasva Tadeva brahma

Tat vijijñāsasva (you should know that) yato vā (from which) imāni (these) bhūtāni (beings) jāyante (are born) yena (by which) jātāni (having been born) jīvanti (live) yat (to which) prayanti (they go) abhisaṃviśanti (and into which they merge) Tadeva (that very) brahma (is Brahman)

Advaita Vedānta (Ādi Śaṅkarācārya): This verse from the Aitareyopaniṣad underscores the non-dual nature of reality, emphasizing that all beings are born from, sustained by, and ultimately merge into Brahman. Śaṅkarācārya, in his commentary on the Upaniṣads, elucidates that the inquiry into the source, sustenance, and final repose of all beings leads to the understanding of Brahman as the ultimate reality. He notes that the ignorance of this truth leads to the cycle of birth and death, while knowledge of Brahman reveals the identity of the individual self (ātman) with the universal Self (Brahman). This verse, therefore, points to the brahman-ātman identity, highlighting the need for Self-inquiry to realize this fundamental unity. By understanding that all phenomena arise from, are sustained by, and return to Brahman, the seeker transcends the limitations of the empirical world and realizes the non-dual essence of existence.

Vaiṣṇava tradition (Rāmānujācārya / Madhvācārya): The Vaiṣṇava tradition interprets this verse in the context of the relationship between the individual self (jīva) and the Supreme Lord (Īśvara). Rāmānujācārya, in his commentary on the Upaniṣads, views this verse as highlighting the dependence of all beings on Īśvara for their existence, sustenance, and ultimate liberation. The source from which beings are born, the sustenance by which they live, and the destination into which they merge are all aspects of Īśvara's divine providence. This understanding fosters a devotional attitude, where the jīva recognizes its inherent dependence on Īśvara and seeks to cultivate love and surrender. Madhvācārya, on the other hand, emphasizes the real distinction between the jīva and Īśvara, while still acknowledging the latter's role as the creator, sustainer, and destroyer of the universe. Both perspectives within the Vaiṣṇava tradition emphasize the centrality of Īśvara in the cosmic process and the jīva's liberation through devotion and knowledge.

Neo-Vedānta (Swami Vivekānanda / S. Rādhākrishnan): This verse from the Aitareyopaniṣad is seen by modern interpreters like Swami Vivekānanda and S. Rādhākrishnan as a call to realize the universal and eternal principles underlying all existence. Vivekānanda, in his lectures and writings, often emphasized the practical application of such Upaniṣadic teachings, urging individuals to seek the source of their being and the ultimate reality that sustains all life. He viewed this verse as an exhortation to look beyond the ephemeral and the mundane, to inquire into the profound mysteries of life and death, and to discover the unity that underlies all diversity. Rādhākrishnan, with his philosophical depth, further expounded on the significance of this inquiry, suggesting that it leads to a realization of the human condition that is both liberating and unifying. By contemplating the origin, sustenance, and final repose of all beings, individuals can transcend petty differences and recognize their shared humanity, fostering a sense of global citizenship and universal empathy.

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