Before i tell you the purpose of fast... i will say that a normal human body can survive without food and water for quite a long time for atleast three days... so its not that human body will malfunction if its not provided food or water for half day or so... rather there are alot of scientific benefits of fasting such as helping in eliminating cancerous cells from the body etc... but the question is what is the spirtual reason for fasting...even though the body can survive for this time period without eating and drinking because of the meals before and after the fast....so from the spirtual point of view fasting is not just about not eating or drinking its more about refraining one self from negative habits of ones life and to show the best character of oneself... its more about getting connected to the higher consciousness, the Creator by connecting with the created by empathizing with them through thirst and hunger... when we start feeling thirsty or hungry after 10 hours of fasting and there is still more time to go... at that time empty stomach makes us think about the suffering humanity... the little kids in africa who havent eaten since days and those immigrants from the lands that are being bombarded, stranded in the middle of sea or that old man in the street curled up in a corner almost unseen who havent eaten a single meal till his stomach is full in years let alone nutrient sufficient diet ... thats when epiphany dawns over... when we taste the 100th part of their hardships and thats what urges us to help them with words and actions... thus connecting ourselves with them... even if its done on a small scale like sharing our after fast meal with that bright eyed, goofily smiling girl dressed in rags sitting outside the park, not turning up our nose at the sight of her dirty hands rather accepting her and loving her as a human being... thats the purpose of the fast... to seek nearness to Allah the Creator... by loving and caring the created...because one can love God by worshipping privately in their dens... but to obtain God's love we have set our frequency with ones who less blessed with the materialistic world...for God loves those who love his fellowmen as God dwells among His people...
The fast is during the day so that we could only do neccessary activities such as our jobs etc with the little energy we have while keeping ourselves from negativity by asking God to get us through day as He wills and when when the sun goes down... in darkness of the night we could worship and find the light of truth and talk to God about even the smallest things that bothered us or our smallest desire even if its about eating our favourite candy... because i feel that at night i am more awakened... sitting alone pondering upon my own existance makes me feel the presence of higher conscience more clearly...
I hope i have answered your question i did try my best to do so... sorry for this long post... and pardon my english please and if have any other question feel free to ask...
Thanks for reading. Peace.

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