Mantra 18

न जायते म्रियते वा विपश्चिन्नायं कुतश्चिन्न बभूव कश्चित् ।अजो नित्यः शाश्वतोऽयं पुराणो न हन्यते हन्यमाने शरीरे ॥ १८ ॥

In plain words

The wise/discerning one is not born, nor does he die; he did not come into being from anywhere, nor did anyone come to be from him. Unborn, eternal, everlasting, this ancient one is not slain when the body is slain.