the concept of 'Jigar'

For those who are familiar with hindi/urdu songs, ghazals etc are well-versed with the usage of 'jigar' in typical love songs. I might be wrong but most of the people mistake it for 'heart' and those who know its english translation take it to be an exceptional usage in poetry.

"nazar ke saamne, jigar ke paas
koi rehta hai wo ho tum"

If we consider this chartbuster hit from Aashiqui, it would translate to 'you stay close to my gaze, close to my liver'. Now, I would not want my beloved to be close to my liver. So, what is the deal. The usage has become popular since the ancient times of urdu maestros who used the term for quite a different reference, which has nothing to do with gastric functionalities at all.

If I may quote from a web reference - "In ghazal physiology, the liver is the organ that makes fresh blood; thus it's an emblem of fortitude, steadfastness, endurance over time. The heart, by contrast is always consuming blood: bleeding constantly, pumping blood to the eyes so the lover can weep tears of blood, and then tearing itself into fragments as a sign of its proper lover-like self-destruction. For the heart to be done for is an initial state of passion, since more blood can be sent along from the liver. But when the liver is finished, the game is up."

Beautifully put by the author. I think that clarifies it nicely for all of us who keep wondering about usage of 'jaan-e-jigar' etc again and again.

Let the thought sink in with few ashaar-

"chak jigar ke see lete hain,
jaise bhi ho jee lete hain"

"aashiqui sabr talab aur tamanna betaab
dil ka kya rang karun, khoon-e-jigar hone tak"