Lord Krishna tells Arjuna as per Bhagwat Gita that Individual Soul is Immortal. It tells all of us with conviction that we are an Immortal Soul & not a mortal body. We shall survive after death also & we as a Soul shall live forever, births after births.
As per Lord Krishna, one Soul present in a body goes through different phases of childhood, youth and old age, so also does that Soul pass into another body; the wise man does not grieve thereat. Know Lord Krishna days that all powerful, Supersoul is indestructible, by whom all this is world is pervaded. None can cause the destruction of That Supersoul, the Imperishable. As we casts off worn-out clothes and puts on new ones, so also the embodied Soul
in this body casts off worn-out bodies and enters others bodies that are new. This rebirth cycle goes on like that & has been going on like that for centuries.
As per Lord Krishna, very sharp weapons cannot cut this soul, nor fire can burn It water cannot wet It & wind cannot dry it. So ones Soul cannot be cut by weapons, burnt by fire, wetted by water nor dried up by air. It is eternal, all-pervasive, same at all times, ancient and immovable, Some people sees the embodied Soul with wonder; some other speaks of It as a wonder; some other hears of It as wonderful; yet, there are many who having heard also, does not understand It at all.
Jai Shri Krishna