Mandukya Karika 3.21
Sanskrit Verse
न भवत्यमृतं मर्त्यं न मर्त्यममृतं तथा ।
प्रकृतेरन्यथाभावो न कथंचिद्भविष्यति ॥ २१ ॥
Transliteration
na bhavatyamṛtaṃ martyaṃ na martyamamṛtaṃ tathā |
prakṛteranyathābhāvo na kathaṃcidbhaviṣyati || 21 ||
Translation
The immortal cannot become mortal, nor can the mortal ever become immortal. For, it is never possible for a thing to change its nature.

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