B.G 2.21
वेदाविनाशिनं नित्यं य एनमजमव्ययम् । कथं स पुरुषः पार्थ कं घातयति हन्ति कम् ॥ २-२१॥
vedāvināśinaṃ nityaṃ ya enamajamavyayam । kathaṃ sa puruṣaḥ pārtha kaṃ ghātayati hanti kam ॥ 2-21॥
[वेद (veda) - knows; अविनाशिनम् (avināśinam) - indestructible; नित्यम् (nityam) - eternal; यः (yaḥ) - who; एनम् (enam) - this; अजम् (ajam) - unborn; अव्ययम् (avyayam) - immutable; कथम् (katham) - how; सः (saḥ) - he; पुरुषः (puruṣaḥ) - person; पार्थ (pārtha) - O son of Pritha; कम् (kam) - whom; घातयति (ghātayati) - causes to kill; हन्ति (hanti) - kills; कम् (kam) - whom;]
(O son of Pritha, how can a person who understands the soul to be indestructible, eternal, unborn, and immutable, cause anyone to be killed or kill anyone?)
O Arjuna, how can the Jīva who knows thus the Indestructible Lord to be (the doer), ever existing, unborn and unchangeable, think of being killed or hurting another?
Gīta Bhāshya 2.21
The words 'avinashina' and 'nitya' refer to the Lord. Word 'nashtha' is commonly used to address Jīva, as it means tainted with defect. The word 'Vēda' refers to the imparted knowledge till previous verse, that the Lord is the doer of all acts and Jīva is not an independent agent.
अतो य एवं वेद स कथं कं घातयति हन्ति वा। अविनाशिनं नैमित्तिकनाशरहितम्। नित्यं स्वाभाविकनाशरहितम् अथवा अविनाशिनं दोषयोगरहितम्। नित्यं सदा भाविनम्। इति सर्वत्र विवेकः । दोषयुक्त पुरुषादिषु नष्टशब्दप्रयोगात्॥ २१ ॥
ato ya evaṃ veda sa kathaṃ kaṃ ghātayati hanti vā। avināśinaṃ naimittikanāśarahitam। nityaṃ svābhāvikanāśarahitam athavā avināśinaṃ doṣayogarahitam। nityaṃ sadā bhāvinam। iti sarvatra vivekaḥ । doṣayukta puruṣādiṣu naṣṭaśabdaprayogāt॥ 21 ॥
[अतः (ataḥ) - therefore; यः (yaḥ) - who; एवम् (evam) - thus; वेद (veda) - knows; सः (saḥ) - he; कथम् (katham) - how; कम् (kam) - whom; घातयति (ghātayati) - causes to kill; हन्ति (hanti) - kills; वा (vā) - or; अविनाशिनम् (avināśinam) - indestructible; नैमित्तिकनाशरहितम् (naimittikanāśarahitam) - free from incidental destruction; नित्यम् (nityam) - eternal; स्वाभाविकनाशरहितम् (svābhāvikanāśarahitam) - free from natural destruction; अथवा (athavā) - or; अविनाशिनम् (avināśinam) - indestructible; दोषयोगरहितम् (doṣayogarahitam) - free from defects; नित्यम् (nityam) - eternal; सदा (sadā) - always; भाविनम् (bhāvinam) - existing; इति (iti) - thus; सर्वत्र (sarvatra) - everywhere; विवेकः (vivekaḥ) - discernment; दोषयुक्त (doṣayukta) - defective; पुरुषादिषु (puruṣādiṣu) - in persons, etc.; नष्टशब्दप्रयोगात् (naṣṭaśabdaprayogāt) - due to the use of the word 'destroyed';]
(Therefore, one who understands this knowledge does not cause harm or kill anyone. The soul is indestructible, free from incidental and natural destruction, and devoid of defects. It is eternal and always exists. Thus, discernment is present everywhere, even in the use of the word 'destroyed' concerning defective individuals.)
How can one who understands thus (Jîva to be eternal and dependent) think of killing or causing another to kill?
"avinâshina" - means one who does not have a destruction of the form; and "nitya" - means one who does not have a destruction of original nature;
or
"avinâshina" - means one who is untouched by defects, and 'nitya' - means one who exists always. Above said is common wisdom. As Jîva is tainted with defects, the word 'nashta' is used to address it.
Gīta Tātparya 2.21
'avinashina' indicates lord without destruction of his body, 'nitya' indicates non-variance in his essential nature. The agency must always primarily be attributed to the Lord and only the ignorant attribute it to themselves.
अविनाशिनं शरीरापायादिवर्जितम्। नित्यं स्वरूपतः। एनं परमेश्वरम्।
avināśinaṃ śarīrāpāyādivarjitam। nityaṃ svarūpataḥ। enaṃ parameśvaram।
[अविनाशिनं (avināśinam) - indestructible; शरीर (śarīra) - body; अपाय (apāya) - destruction; अदिवर्जितम् (adivarjitam) - free from; नित्यं (nityaṃ) - eternal; स्वरूपतः (svarūpataḥ) - by nature; एनं (enaṃ) - this; परमेश्वरम् (parameśvaram) - Supreme Lord;]
(The Supreme Lord is indestructible, free from bodily destruction, and eternal by nature.)
The word 'avinashinam' indicates one who is devoid of defects such as the destruction of the body; 'nityam' indicates one's own essence; 'enam' is a reference to the supreme lord.
"कर्तृत्वं तु स्वतन्त्रत्वं तदेकस्य हरेर्भवेत् ।तच्चाव्ययं तस्य जानन् कथं कर्ता स्वयं भवेत्।"
"kartṛtvaṃ tu svatantratvaṃ tadekasya harerbhavet ।taccāvyayaṃ tasya jānan kathaṃ kartā svayaṃ bhavet।"
[कर्तृत्वं (kartṛtvaṃ) - agency; तु (tu) - but; स्वतन्त्रत्वं (svatantratvaṃ) - independence; तत् (tat) - that; एकस्य (ekasya) - of the one; हरेः (hareḥ) - of Hari; भवेत् (bhavet) - is; तत् (tat) - that; च (ca) - and; अव्ययम् (avyayam) - unchanging; तस्य (tasya) - of him; जानन् (jānan) - knowing; कथम् (katham) - how; कर्ता (kartā) - doer; स्वयम् (svayam) - himself; भवेत् (bhavet) - can be;]
(Agency and independence belong solely to Hari; knowing this unchanging truth, how can one consider oneself the doer?)
"The notion of agency is nothing but freedom to do. It exists in Lord Hari alone. It is present in Him always, without destruction. How can one with this understanding think of himself as a doer?"
-इति परमश्रुतिः।
-iti paramaśrutiḥ।
[इति (iti) - thus; परम (parama) - supreme; श्रुतिः (śrutiḥ) - revelation;]
- thus states Parama sruti
अन्यथा अविनाशिनं नित्यमिति पुनरुक्तिः ॥२१॥
anyathā avināśinaṃ nityamiti punaruktiḥ ॥21॥
[अन्यथा (anyathā) - otherwise; अविनाशिनं (avināśinaṃ) - indestructible; नित्यम् (nityam) - eternal; इति (iti) - thus; पुनरुक्तिः (punaruktiḥ) - repetition;]
(Otherwise, it is a repetition of the eternal indestructible nature.)
If not interpreted this way, the words 'avinashina' and 'nitya' providing same meaning results in redundancy error.