B.G 2.30
देही नित्यमवध्योऽयं देहे सर्वस्य भारत। तस्मात् सर्वाणि भूतानि न त्वं शोचितुमर्हसि ॥२-३०॥
dehī nityamavadhyo'yaṁ dehe sarvasya bhārata। tasmāt sarvāṇi bhūtāni na tvaṁ śocitumarhasi ॥2-30॥
O Bharata, this embodied being stationed in this body, is everlasting and indestructible everywhere. Therefore, you should not grieve for any creature.
Gīta Tātparya 2.30
The being is eternal because of the Lord, not because of his own capacity
How is the embodied indestructible? The Lord of all beings stations Himself as the protector of the subtle and gross bodies. Hence, it is indestructible, not because of its own strength at any given time.
"The substance, the movement, the time; the essential nature, the being - all these exist because of his grace and cease to exist if he shows reluctance."
-states Bhagavata
"Lord Vishnu stations himself there and there, and protects the eternals as eternal. Similarly, He keeps the non-eternal entities as non eternal. Thus, eternal and non-eternals come into being. As he controls the existent and non-existent, he is called best among the beings."
- thus states Padma Purāna
