Mundaka 4.06

यस्मिन् द्यौः पृथिवी चान्तरिक्षमोतं मनः सह प्राणैश्च सर्वैः। तमेवैकं जानथ आत्मानमन्या वाचो विमुञ्चथामृतस्यैष सेतुः ॥६॥

yasmin dyauḥ pṛthivī cāntarikṣamotaṃ manaḥ saha prāṇaiśca sarvaiḥ। tamevaikaṃ jānatha ātmānamanyā vāco vimuñcathāmṛtasyaaiṣa setuḥ ॥6॥

[यस्मिन् (yasmin) - in which; द्यौः (dyauḥ) - heaven; पृथिवी (pṛthivī) - earth; च (ca) - and; अन्तरिक्षम् (antarikṣam) - sky; उतम् (otam) - woven; मनः (manaḥ) - mind; सह (saha) - with; प्राणैः (prāṇaiḥ) - life-breath; च (ca) - and; सर्वैः (sarvaiḥ) - all; तम् (tam) - that; एव (eva) - only; एकम् (ekam) - one; जानथ (jānatha) - know; आत्मानम् (ātmānam) - one-self / the being; अन्या (anyā) - other; वाचः (vācaḥ) - utterances / expressions; विमुञ्चथ (vimuñcatha) - abandon; अमृतस्य (amṛtasya) - of immortality; एषः (eṣaḥ) - this; सेतुः (setuḥ) - bridge;]

Into which heaven, earth, and sky are woven, along with the mind, life-breath and all, know that one alone as the one-self, the being; abandon other utterances as this-one is the bridge towards immortality.

Bhāshya 4.06

The term 'amṛtasya' i.e. immortality, is used to indicate the bridge towards liberation. Same is substantiated through Brahmasutra 1.3.2 and Vishnu Sahasranama.

अमृतस्य मुक्तस्य सेतुः। "मुक्तोपसृप्यव्यपदेशात्", "मुक्तानां परमा गतिः" इत्यादेः॥

amṛtasya muktasya setuḥ। "muktopasṛpyavyapadeśāt", "muktānāṃ paramā gatiḥ" ityādeḥ॥

[अमृतस्य (amṛtasya) - of the immortal; मुक्तस्य (muktasya) - of the liberated; सेतुः (setuḥ) - bridge; मुक्तोपसृप्यव्यपदेशात् (muktopasṛpyavyapadeśāt) - from the designation of approaching the liberated; मुक्तानां (muktānāṃ) - of the liberated ones; परमा (paramā) - supreme; गतिः (gatiḥ) - goal; इत्यादेः (ityādeḥ) - and so on;]

The term 'amṛtasya' i.e. immortality, is used to indicate the bridge towards liberation. The brahmasutra (1.3.2) stating, "As declared, is to be attained by the liberated", and the Vishnu Sahasranāma stating, "He is the ultimate resort of the liberated", reiterate this concept.