Shatapatha Brahmana 10.1.3.4

10.1.3.4

tadetā vā asya tāḥ pañca martyāstanva āsaṃloma tvaṅmāṃsamasthi majjāthaitā amṛtā mano vākprāṇaścakṣuḥ śrotram

And, indeed, these five forms (bodily parts) of him are mortal--the hair on the mouth, the skin, the flesh, the bone, and the marrow; and these are immortal--the mind, the voice, the vital air; the eye, and the ear.