In the Qudsi Hadith, Allah The Almighty Says (What means): "Every deed of the son of Adam is multiplied: a good deed is multiplied tenfold up to seven hundred times, except for fasting; it is for Me, and I will reward it. He leaves his desires and his food for My sake..." [Moslim].
In this hadith, Allah excludes fasting from the deeds that have a fixed reward. All deeds are multiplied: a good deed by ten times, up to seven hundred times, except fasting. Allah multiplies its reward without any specific limit.
It is understood that the fasting referred to here is the fasting that Allah has commanded, not merely refraining from food and drink, as is the case with many people's fasting. However, why did Allah single out fasting from all other deeds with this special distinction when He Said (What means): "Except for fasting; it is for Me, and I will reward it"?
If we reflect on the reality of fasting and the difference between it and other acts of worship, we can deduce some of the wisdoms for which Allah granted the fasting person this great virtue. Among these wisdoms are:
First: Fasting is a secret between the servant and his Lord, known only by Allah. A person may show off in their prayer or other acts of worship because they are visible actions, but they cannot show off in fasting — meaning, they cannot display it to people for recognition and praise. It has been narrated: "Fasting has no show-off" [Al-Bayhaqi in "Shu'ab Al-Iman"]. Fasting consists of two elements: refraining from food, drink, and other desires, and an intention held in the heart, which only Allah Knows. Therefore, it is fitting that the matter of fasting remains between the servant and his Lord, and that Allah singles it out by attributing it to Himself, unlike other deeds.
Second: Fasting is the only act of worship in which a person abandons all their desires for the sake of Allah. For example, when a person enters the state of Ihram (Ritual consecration) for Hajj or Umrah, they only give up some desires, like intimacy and beautification, while other desires, like food and drink, remain permissible. Similarly, when a person gives Zakat (Alms) or charity, they only give up the desire for wealth.
Nevertheless, in fasting, as mentioned in the previous hadith: "He leaves his desires and his food for My sake." This phrase explains the reason behind fasting's unique reward — the fasting person leaves multiple desires, and the reward for abandoning each one is known only to Allah.
It may be argued that prayer also involves leaving all desires, just like fasting. However, the difference lies in the duration — prayer lasts only a few minutes, so the person does not suffer the deprivation of food and drink, whereas fasting lasts the entire day.
Third: It is narrated from the Prophet (peace be upon him) that he said: "Fasting is half of patience" [Reported by Ahmad, Ibn Majah, and Al-Tirmidhi, who graded it as sound]. Patience is of three types: patience in performing acts of worship, patience in refraining from what Allah has forbidden, and patience in enduring trials.
All three types of patience come together in fasting: patience in performing an act of worship, patience in abstaining from forbidden desires, and patience in enduring the hunger and thirst that occur during fasting. Thus, fasting encompasses all forms of patience. Allah Says (What means): "Indeed, the patient will be given their reward without measure" [Az-Zumar/10]. One meaning of "without measure" is an immense reward, which is attained through fasting.
Fourth: Fasting is a training ground for preparing a person for the future. When one enters this school of fasting, their intention is to be righteous and committed in the present and the future. The fasting person holds two intentions: one for the present moment and one for future commitment. Therefore, they deserve the reward for both their current fasting and their future resolve. This resolve and intention are known only to Allah, and their sincerity can only be judged by Him. Thus, the reward for them is from Allah alone.
Fifth: Fasting links the lawful and unlawful to time. What was permissible yesterday becomes forbidden during the day, and what was forbidden a few moments ago becomes lawful with the call to Maghrib (Sunset) prayer. This demonstrates the ultimate submission and obedience to Allah.
The fasting person refrains from their desires during the day out of obedience to Allah, and they hasten to them at night, also out of obedience. They abstain and return to their desires only in response to Allah's command. They are obedient in both states. For such a person, it is hoped that they will be among those who are told (What means): "Eat and drink in satisfaction for what you put forth in days past" [Al-Haqqah/24].
