“antavanta ime deha
tasmad yudhyasva bharata” (Bhagwat Gita: Chapter Two verse 18)
According to Bhagwat Gita, the Soul, or Atman, neither slays not can it be slain (Chapter 2.19).
“ya enam vetti hantaram
yas chainam manyate hatam
ubhau tau na vijanito
nayam hanti na hanyate” (Bhagwat Gita: Chapter Two verse 19)
According to Bhagwat Gita, the Soul, or Atman, is never born, never dies and after coming into existence never ceases to be. It is nitya (always), shasvatah (permanent) and purana (very ancient) (Chapter 2.20).
“na jayate mriyate va kadacin
nayam bhutva bhavita va na bhuyah
ajo nityah sasvato ’yam purano
na hanyate hanyamane sarire” (Bhagwat Gita: Chapter Two verse 20)
According to Bhagwat Gita, the Soul, or Atman, does not suffer & cannot be tainted. At the time of death it does not die, but leaves the body and enters into a new one (Chapter 2.22).
“vasamsi jirnani yatha vihaya
navani grhnati naro ’parani
tatha sarirani vihaya jirnany
anyani samyati navani dehi” (Bhagwat Gita: Chapter Two verse 22)
According to Bhagwat Gita, the Soul, or Atman has the properties that Weapons cannot pierce it, fire cannot burn it, water cannot moisten it and wind cannot dry it (Chapter 2.23).
nainam dahati pavakah
na chainam kledayanty apo
na sosayati marutah” (Bhagwat Gita: Chapter Two verse 23)
“Sri Krishna said: The soul can never be cut to pieces by any weapon, nor burned by fire, nor moistened by water, nor withered by the wind.”
According to Bhagwat Gita, the Soul, or Atman, is impenetrable, incombustible, all pervading, stable and immobile (Chapter 2.24).
akledyo ’sosya eva cha
nityah sarva-gatah sthanur
achalo ’yam sanatanah” (Bhagwat Gita: Chapter Two verse 24)
“Sri Krishna said: This individual soul is unbreakable and insoluble, and can be neither burned nor dried. He is everlasting, present everywhere, unchangeable, immovable and eternally the same.”
According to Bhagwat Gita, the Soul, or Atman, is invisible, imperceptible and immutable (Chapter 2.25).
avikaryo ’yam ucyate
tasmad evam viditvainam
nanusocitum arhasi” (Bhagwat Gita: Chapter Two verse 25)
“Sri Krishna said: It is said that the soul is invisible, inconceivable and immutable. Knowing this, you should not grieve for the body.”
Lord Krishna knew the limitations of human consciousness to gauge the true nature of the inner soul. So in the Bhagwat Gita it concurs that no one can exactly know what a soul is. Someone looks at It with great surprise, another speaks about It with great surprise, some another hears about It with incredulity and yet another after hearing about It knows it not (Chapter 2.29).
ascharya-vad vadati tathaiva chanyah
ascharya-vac chainam anyah srnoti
srutvapy enam veda na chaiva kascit” (Bhagwat Gita: Chapter Two verse 29)
“Sri Krishna said: Some look on the soul as amazing, some describe him as amazing, and some hear of him as amazing, while others, even after hearing about him, cannot understand him at all.”
So in this way Soul is a Mysterious thing & can be understood if you have faith in God & in religious scriptures.
Jai Shri Krishna