Aatmaa (The Soul)

Soul is defined as the immaterial essence, animating principle, or actuating cause of an individual life. Let's visit some of the verses in Geeta which describe the soul.

It is present throuh childhood, youth and old age and passes to another body upon death.

देहिनोऽस्मिन्यथा देहे कौमारं यौवनं जरा ।
तथा देहान्तरप्राप्तिर्धीरस्तत्र न मुह्यति ॥२:१३॥

Lord Krishna says to Arjun:
As it is embodied in the body through the childhood, youth and old age, so does it acquire a different body upon death; the wise are not bewildered.

Those who think the soul kills or is killed, they are not aware.

य एनं वेत्ति हन्तारं यश्चैनं मन्यते हतम् ।
उभौ तौ न विजानीतो नायं हन्ति न हन्यते ॥२:१९॥

Lord Krishna says to Arjun:
He who regards this (soul) as killer and who thinks this is killed; both of them do not know that it neither kills nor is it killed.

The soul is unborn, eternal and primeval. It neither kills nor is it killed.

न जायते म्रियते वा कदाचिन्
नायं भुत्वा भविता वा न भूय​: ।
अजो नित्यः शाश्वतोऽयं पुराणो
न हन्यते हन्यमाने शरीरे ॥२:२०॥

Lord Krishna says to Arjun:
It (soul) is neither born nor it dies. Neither was it there for some time only or will it be there for some time only or cease to exist at all. This (soul) is unborn, always present, eternal and primeval. It does not get struck or is being killed in the body.

Just like people change the worn clothes, so does the soul abandon the old body enters new one.

वासांसि जीर्णानि यथा विहाय
​ नवानि गृह्णाति नरोऽपराणि ।
तथा शरीराणि विहाय जीर्णान्य​-
न्यानि संयाति नवानि देही ॥२:२२॥

Lord Krishna says to Arjun:
Just as the person puts on another new garment leaving behind the worn out garment, so does the soul leave behind the worn-out body and joins another new body.

The soul can't be destroyed by weapons, fire, water or air.

नैनं छिन्दन्ति शस्त्राणि नैनं दहति पावक​: ।
न चैनं क्लेदयन्त्यापो न शोषयति मारुत​: ॥२:२३॥

Lord Krishna says to Arjun:
Neither can this be cut apart with weapons nor does it burn in fire. Neither does it get wet with water nor can the air dry it.

It is undestroyable, spread everywhere and perpetually stationary.

अच्छेद्योऽयमदाह्योऽयमक्लेद्द्योऽशोष्य एव च​ ।
नित्य​: सर्वगतः स्थाणुरचलोऽयं सनातन: ॥२:२४॥

Lord Krishna says to Arjun:
This soul is really impenetrable, unburnable, unwettable and unabsorbable. It is always present, ubiquitous, standing firmly and unmovable in perpetuity.

It's unmanifest, unfathomable and unchangeable (or defectless).

अव्यक्त्तोऽयमचिन्त्योऽयमविकार्योऽयमुच्यते ।
तस्मादेवं विदित्वैनं नानुशोचितुमर्हसि ॥२:२५॥

Lord Krishna says to Arjun:
Unmanifest it is, unfathomable it is and unchangeable (or defectless) it is, it has been said. Therefore, having known thus, you do not deserve (or befit) to be lamenting.

Didn't understand anything? You're not alone!

आश्चर्यवत्पश्यति कश्चिदेनम्
आश्चर्यवद्वदति तथैव चान्यः ।
आश्चर्यवच्चैनमन्यः शृणोति
श्रुत्वाप्येनं वेद न चैव कश्चित् ॥२:२९॥

Lord Krishna says to Arjun:
Someone sees this with astonishment, another speaks with amusement about this, the other hears about this with amusement and yet another, even after hearing about this, does not understand this.