Saum is actually a sort of military training for making the momineen capable of bearing the difficulties of jihad, which is the struggle for establishing Allah’s way of life.
The Quran has itself said:
So that you become capable of looking after the laws of Allah
لَعَ لَّکُمْ تَتَّقُوْنَ
so that you can establish the laws of Allah as given in the Quran and replace the system based on man made laws
لَتُکَبِّرُوْا ال لّه عَلٰی مَاهَدَاکُمْ
so that your efforts can produce full results
وَلَعَلَّکُمْ تَشْکُ رُوْنَ
صَا ئِمٌ “ ” (saa’imun): one who abstains from the wrong path, or one who fasts (33:35), or one who controls
himself, and one who stays within the limits defined by the Quran. The Quran explains the purpose of its
injunctions and in the case of fasting it declares that the purpose is to become righteous as defined in the
Quran e.g. (2:183, 2:177, 23:1-9, 17:31-39). At an individual level one should asses the level of selfdevelopment
on the first of Ramadan and then asses that after completion of the training through fasting
what improvements have been made in the personality. The Quran recognises the difficulty of keeping
fast and emphasises its importance through the effects it will have on the character development.
Therefore it is important to understand the reason behind this value to get maximum benefit and not to
follow it as a mere ritual as the later will not contribute to any improvement despite fasting and remaining
hungry/thirsty will result in no self-development.