Atman (Soul) is Existence –Consciousness-Bliss.
Atman is to be understood as follows:
(1) It is the Witness of the three states of consciousness consisting of waking, dream and deep sleep.
(2) It is beyond the five sheaths constituting annamaya, pranamaya, manomaya, vijnanamaya, anandamaya.
(3) It exists always whether in the past, present or future.
(4) It is the consciousness principle .
(5) It is ever in the state of bliss.
(6) It is different from the gross body.
(7) It is different from the subtle body.
(8) It is different from the Causal body.
(9) Weapons cannot cut it.
(10) Air cannot dry it.
(11) Fire cannot burn it.
(12) It is unborn.
(13) It is beyond all modifications.