Om Namasivaya Nama:
He who reaches the Self and merges with it is the liberated one. In other words search like a painter who uses Munja Grass. All sense objects should be carefully handled to derive at the core actionless Atma.
Acharya explains in depth by each Sheath (Kosa), to begin with Annamaya Kosa (Food Sheath).
Body can't be Self-existing because it depends on food and pure air (Prana). The physical body represents Food and Prana. It is made up of 7 dhathus (by products of Pancha-bhoothas) due to which it can't be pure like Athma.
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