In plain words
Just as, however many times, and in whatever way, I cut off my nails and cast them away, in that very same way I can relinquish my gross body hundreds of thousands of times over. But my subtle body will remain standing — that will remain. This is the supreme secret that our Bharatiya highest-teaching stream declares. Examined further, 'man' means a gross body, a subtle body, and a jīva all combined together — a living being. According to Vedāntic philosophy, the jīva is eternal, like God. Nature too is indeed eternal, but exists undergoing changes. The substance of prāṇa and ākāśa, which is the root of Nature, is indeed eternal, but it always keeps turning into various forms. The jīvātma, however, was not fashioned in either ākāśa or prāṇa. It is not a physical thing at all. It is therefore eternal. It did not come about because of the union of prāṇa and ākāśa. An uncompounded substance cannot have destruction.
Because destruction means nothing more than splitting into constituent parts. Since the gross body is a union of prāṇa and ākāśa, separation is inescapable for it. In that same way, the subtle body too meets with separation, but that happens after a long interval of time. Since the jīva is an uncompounded thing, it has no destruction, that is, no separation. In the same way, it has no birth either — it cannot. For an uncompounded thing to be born at all is impossible. All of Nature, made up of lakhs upon lakhs of things, remains subject to God's will. God, omniscient and all-pervading, is at work through Nature night and day.