Om Namasivaya nama:
Listen carefully! This subtle body is also called Linga Sariram. This Sarira is made out of subtle elements of possessed out of inclinations (Vaasanaas) and it causes the individual body to experience the fruits of past deeds / actions (Fruits of Karma). It is the state of beginningless state on the Self due to its on ignorance (Agnaana). In other words there is no beginning nor end to this Self because time does not exists at the time of its beginning.
Sloka 98 & 99:
Further to the Gross body explanation (where this can be realized while on Awaken state / Jagradavastha) now Acharya explain the state of Subtle Body (Sookshma Sariram). Easy way to see the subtle body is during the Swapna (Dream state) avastha, it will be distinctively expressed in its own. Intellectual (Budhi of Anktakarana) is the agent for these experiences gathered during waking state. In this condition / situation the Supreme Self witness the happening and shine its own glory as unattached to the experience undergone by intellectual. Since it is un-attached it is not getting tamed by any action that it apparent conditioning may perform. The Paramatman is absolutely unattached and only witness as onlooker neither it get involved in joy nor sad. The link for Atma to the Jeeva which lives inside the body (actually body lives in Atma..just like a tree live inside the small seed, may be in real life difficult to believe) is through its Intellectual.
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