B.G 2.17

avināśi tu tadviddhi yena sarvamidaṃ tatam । vināśamavyayasyāsya na kaścitkartumarhati ॥ 2-17॥

But know that to be indestructible by which all this is pervaded. The destruction of this imperishable is impossible and beyond anyone's ability.

Gīta Bhāshya 2.17

The destruction of such everlasting principles is denied by using the word 'avinashina'. Its unchanging nature is highlighted by the word 'avyaya'.

kiṁ bahunā । yad deśatonantaṁ tannityameva vedādyanyadapītyāha - avināśīti । nāpi śāpādinā vināśa ityāha – vināśamiti । avyayaṁ ca tat ॥ 17 ॥

What are those others (without destruction)? Those that are not bound by space, that are everlasting like the Vedas, are indicated by the word 'avinashina'. Their destruction through instrumentality is denied by using the word 'vinasham', i.e. destruction. The word 'avyaya', i.e. unchanging, is used to address such principles.

Gīta Tātparya 2.17

Destruction is of four types: destruction of the body, possession of misery, incompleteness, and non-being. Though other principles are imperishable in some dimensions, only the Lord is imperishable in all four dimensions. The space, time and qualities are the different dimensions. On all these dimensions, Lord Hari alone is complete with all auspicious qualities. The word 'tu' is used to qualify this speciality of the Lord.

yadyapi nityatvaṁ jīvasyāpyasti । tathāpi sarvaprakāreṇāvināśitvaṁ viṣṇoreveti tuśabdaḥ ।

Even though eternality is indicated for individual beings, all kinds of everlasting qualities exist in the Lord Vishnu alone. This is specified by using the word 'tu'.

"anityatvaṁ dehahānirduḥkhaprāptirapūrṇatā । nāśaścaturvidhaḥ proktastadabhāvo hareḥ sadā । tadanyeṣāṁ tu sarveṣāṁ nāśāḥ kecid bhavanti hi॥"

"Impermanence, loss of the body, experience of suffering, and incompleteness—these four kinds of destruction are declared; the absence of these is always with Hari, but for all others, some forms of destruction do occur."

iti mahāvārāhe ।

- states Mahavaraha Purana

"deśataḥ kālataścaiva guṇataśca tridhā titiḥ । sā samastā harereva na hyanye pūrṇasadguṇāḥ॥"

"The space, time, and qualities are the different dimensions. On all these dimensions, Lord Hari alone is complete with all auspicious qualities; no other."

iti paramaśrutiḥ ॥17॥

–states Paramashruti, the Vedic testimonial.