Bhagavad Gita 2.21

He who knows the Spirit to be indestructible, immortal, unborn, and always the same, how should he kill or cause to be killed?

वेदाविनाशिनं नित्यं य एनमजमव्ययम्।
कथं स पुरुषः पार्थ कं घातयति हन्ति कम्॥

vedāvināśinaṃ nityaṃ ya enamajamavyayam|
kathaṃ sa puruṣaḥ pārtha kaṃ ghātayati hanti kam||

English translation (above): Shri Purohit Swami (1935), public domain. Sanskrit text via github.com/gita/gita (Unlicense).