Tataḥ śataguṇā varṇo vavṛdhe puruṣa-sattamaḥ Na ca tasya kaśāgraṃ tat-prāṇād api dṛśyate

Tataḥ (then) puruṣa-sattamaḥ (the best of men) varṇoḥ (the color) śataguṇā (one hundred times) vavṛdhe (increased) Na (not) ca (and) tasya (his) kaśāgraṃ (a hair's tip) api (even) tat-prāṇād (than his life) dṛśyate (is seen)

Advaita Vedānta (Ādi Śaṅkarācārya): This verse illustrates the non-dual nature of reality, where the individual self (jīva) merges with the ultimate reality (Brahman). Shankara, in his commentary on the Brihadaranyaka Upanishad, explains that the jīva, when realized, loses its individuality and becomes one with Brahman. Similarly, in this verse, the best of men (puruṣasattamaḥ) increases a hundredfold in brilliance, indicating the expansion of the self beyond its limited individual form. The phrase 'not the tip of a hair nor even his life-breath could be seen' suggests the transcendence of the physical and vital aspects of the self, pointing to the identity of the individual self with the all-pervading Brahman. This interpretation is in line with Shankara's reasoning in the Taittiriya Upanishad, where he explains that the self, when realized, is beyond all limitations and attributes.

Vaiṣṇava tradition (Rāmānujācārya / Madhvācārya): In the Vaiṣṇava tradition, this verse is seen as an illustration of the relationship between the jīva and Īśvara. Rāmānujācārya, in his commentary on the Brahma Sutras, explains that the jīva, when devoted to Īśvara, experiences a transformation, where its inherent qualities are enhanced. The 'hundredfold increase in brilliance' can be seen as a metaphor for the jīva's spiritual growth, made possible by its devotion to Īśvara. The phrase 'not the tip of a hair nor even his life-breath could be seen' suggests the complete surrender of the jīva to Īśvara, where the individual self is transcended, and the jīva becomes one with the divine. This interpretation is in line with Rāmānujācārya's concept of 'aprthak-siddhi,' where the jīva, though distinct from Īśvara, experiences a direct and intimate relationship with the divine.

Neo-Vedānta (Swami Vivekānanda / S. Rādhākrishnan): This verse has a profound message for contemporary life. As Swami Vivekānanda explains in his lectures on the Upanishads, the expansion of the self beyond its limited individual form is a universal human aspiration. The 'hundredfold increase in brilliance' can be seen as a symbol of human potential, where individuals can transcend their limitations and realize their true nature. The phrase 'not the tip of a hair nor even his life-breath could be seen' suggests the importance of self-transcendence, where individual ego and desires are let go, and the individual becomes one with the universal. As S. Rādhākrishnan writes in his book 'The Bhagavadgītā,' this verse points to the ideal of self-realization, where the individual self is transcended, and the universal self is realized. This has practical implications for contemporary life, where individuals can strive for self-transcendence, and realize their true potential, by letting go of their ego and desires.

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