Bhagavad Gita · 2.24

अच्छेद्योऽयमदाह्योऽयमक्लेद्योऽशोष्य एव च।नित्यः सर्वगतः स्थाणुरचलोऽयं सनातनः॥

achchhedyo 'yam adāhyo 'yam akledyo 'śhoṣhya eva cha nityaḥ sarva-gataḥ sthāṇur achalo 'yaṁ sanātanaḥ

The soul is unbreakable and incombustible; it can neither be dampened nor dried. It is everlasting, all-pervading, unchanging, immovable, and eternally the same.

— Bhagavad Gita 2.24

Source: Sacred-Texts.com (Sanskrit) + Bhagavad-Gita.io (translations)