The blessings related to fasting are truly astounding. Those who fast are able to scale the ranks; expiate their sins; tame their desire; give much in charity; engage in a variety of acts of worship; give thanks to their Creator; avoid being swayed by impulses of disobedience and violations; distance themselves from the blazing Fire; and tap on the doors of Paradise. Fasting possesses so many virtues; some of these are presented below.
1. Saa'ihoon: an honourable description
Allah describes the righteous believers in the Qur’aan with many names. One such description is Saa’ihoon. Allah says, ‘The believers whose lives Allah has purchased are) those who repent to Allah, who worship Him, who praise Him, who are the Saa’ihoon, those who bow down (in prayer), who prostrate themselves (in prayer), who enjoin virtue and forbid vice, and who observe the limits set by Allah. And give glad tidings to the believers.' 
Saa’ihoon literally means travellers and many scholars mention that this refers to those who fast. Some scholars of the Arabic language state that the fasting person was named a traveller [saa’ih] because a traveller has no provision with him but eats wherever and whenever he finds food.
2. Fasting has no equivalent
Aboo Umamah relates, ‘I approached the Messenger of Allah and asked, “O Allah’s Messenger, command me with a matter by which Allaah will benefit me” (in another narration, ‘Command me with an action by which I will enter Paradise’) He replied, “Take to fasting for it has no equivalent”.’ 
It was said that smoke (from cooking) was never again noticed during the day in Aboo Umamah’s house and if it was, then people knew for sure he had guests.
3. Allaah claims the action for Himself
This reveals its sublime and dignified status. The Prophet (peace be upon him) said, ‘Allah ‘azza wa jalla said, “Every deed a person does is for his own self except fasting; it is for Me and I compensate for it”.’ 
One reasoning given is that fasting is free of riyaa’, which means to perform an action not solely for Allah but to be noticed by others in order to seek their awe, praise or worldly gain. Ibn al-Jawzi said,
‘All acts of worship are noticeable (by others) when performed and it is rare for it to be free of some tarnishing, except fasting’ 
4. Superiority of reward
Al-Qurtubi discusses the meaning of the aforementioned hadeeth ‘and I compensate for it’. He says,
‘This means that the measure of rewards for actions (in general) are known to people and that they are multiplied anywhere from ten to seven hundred fold to whatever Allah wills, to the exception of fasting as Allah rewards one for it without any pre-determined measure.’ 
‘This is a sign of the immense compensation and rich rewards for it because if al-Kareem (The Most Generous) informs that he will grant an offering without any intermediary, this necessitates its swiftness and merit’. 
5. The suitability of fasting
Allaah is Al-Ghaniyy (The Rich), Al-Qayyoom (The Self-Sustainer and Supporter of all) and As-Samad (The Self-Sufficient Master, Who has no need for food or drink and Whom all creatures need).
‘The lack of need for food and other desires is a characteristic of the Lord, jalla jalaluhu; because a fasting person draws near to Him in a manner appropriate to His own attributes (which) He ascribed to Himself.’
‘The actions of slaves are all in agreement to their own dispositions except for fasting. This is appropriate to one of the characteristics of Al-Haqq (The One True Deity); it is as if He is saying, “My servant draws near to Me with a matter that is connected to one of My attributes”.’ 
6. Fasting expiates sins
The Prophet, salla Allaah 'alayhi wa sallam, said, ‘The trials [fitnah] a person experiences through his family, wealth, self, children and neighbour are expiated by fasting, prayer, charity, commanding virtue and forbidding vice.’ 
7. Praise from Allaah and supplication from the Angels!
The Prophet (peace be upon him) said, ‘Indeed Allaah sends His Salaah (praise, grace, honour, blessings, mercy) and His angels send Salaah (ask Allaah for them to be praised, graced etc.) upon those who take the pre-dawn meal.’ 
If Allaah and His angels send Salaah for those who take the pre-dawn meal, which is an aid to fasting, what do you think about fasting itself?
8. A formidable shield
The Messenger (peace be upon him) said, ‘Fasting is a shield from the punishment of Allaah.’ 
He also said, ‘Fasting is a shield with which a servant protects himself from the Fire.’ 
He also said, ‘Fasting is a shield from the Fire just like one of your shields in battle.’
Al-Manaawi (rahimahullaah) says,
‘A protection in this world from disobedience by curtailing desire and preserving the limbs, and in the Hereafter from the Fire.’ 
Ibn ‘Abd al-Barr (rahimahullaah) stated,
‘As a virtue of fasting, this is surely sufficient for you!’
9. The summer fast
Abu Musa relates,
‘Allah decreed upon Himself that whoever goes thirsty for Him on a hot day, that He would grant him water on the Day of Judgement.’ 
Fasting in summer is a quality of faith because of the length of a summer day and the severity of its heat.
10. The winter fast
The Prophet (peace be upon him) said, ‘Fasting in winter is easy prey.’ 
‘Umar Ibn al-Khattab said,
‘Winter is prey (for the taking) for worshippers.’ 
‘Winter is an excellent time for the believer; its nights are long in which he stands for prayer and its days are short which he fasts’.
11. Al-Rayyaan invites
The Prophet (peace be upon him) said:
‘In Paradise, there are eight doors. One of these doors is called Ar-Rayyaan and only those who fast will enter through it.’ 
‘Indeed there is a door in Paradise called Ar-Rayyaan. Those who fast will enter through it on the Day of Judgement. It is only they who will enter it and when they have entered, it will be closed so that no one else can enter.’ 
‘Rayyaan means to be well-sated with drink, the opposite to thirst; it was named this in compensation for the thirst and hunger endured by those who fasted.’ 
‘Izz al-Din Ibn ‘Abd As-Salaam said,
‘As for the restriction of those entering Paradise through the door of Ar-Rayyaan to only those who fasted, they were set apart because of the distinction and nobility of their worship’ 
12. A fine finale
The Prophet (peace be upon him) said, ‘Whoever passes away on a day he fasts will enter Paradise.’ 
‘I.e., whoever completes his lifetime with a day of fasting either dying while fasting or after having broken the fast for that day, will enter Paradise along with the forerunners and foremost generations or without any previous punishment.’ 
13. An intercessor
The Prophet (peace be upon him) said,
‘Fasting and the Qur'aan will intercede for the servant on the Day of Resurrection. Fasting will say, “My Lord, I forbade him food and desire so accept my intercession for him”. The Qur'aan will say, “My Lord, I prevented him from sleep at night, so accept my intercession for him”. So their intercession will be accepted.’ 
14. Accepted supplication
The Prophet (peace be upon him) said, ‘Three supplications are responded to: the supplication of the one fasting; the one oppressed and the traveller.’ 
He also said, ‘There are three whose supplication will not be rejected: the fasting person at the time of breaking his fast; the just ruler and the supplication of an oppressed person.’ 
15. Two occasions for joy
The Prophet (peace be upon him) said, ‘The fasting person has two occasions for joy, one when he breaks his fast and the other when he meets his Lord.’ 
16. A smell more pleasant than musk
The Prophet (peace be upon him) said that Allaah Almighty said:
‘Every deed a person does is for his own self except fasting; it is for Me and I compensate for it. Indeed, the smell of the fasting person’s mouth is more pleasant to Allaah than that of musk.’ 
17. Fasting prevents distraction
‘Fasting was legislated to tame the desires of the soul and to put a stop to what causes one to be in servitude and enslaved by things; if people continue to satisfy their desires they will be enslaved by things and will be disconnected from Allaah. Fasting severs any connection to devoting servitude to other than Him and delivers freedom from being bound to what one covets; the meaning of freedom is to own things and not for things to own a person. If they do own and control him, wisdom is upturned and what is to be preferred becomes the opposite and what is most lofty becomes the most low...’ 
18. Realising the need for gratitude
Al-Qastalani says concerning the aims and virtues of fasting,
‘It causes one to offer much gratitude for one’s blessings and bounties and to acknowledge the previous blessings of satisfying one's need because of hunger and thirst; this causes one to strive to be grateful since something is truly known by its opposite.’ 
19. Opportunity and incentive to more acts of worship
‘Izz al-Din Ibn ‘Abd al-Salam said,
‘As for the opportunity to engage in more acts of worship, this is because it reminds one of the hunger and thirst of the dwellers of the Fire so it urges one to perform more acts of worship in order to attain salvation from the Fire. As for restraining impulses of disobedience and violations, this is because a soul that has had its fill desires and yearns for disobedience whereas if it is hungry and thirsty it desires food and drink. The desire of the soul for deliverance (from hunger and thirst) and being preoccupied with this is better than its yearning for disobedience and sin. This is why some of the early generations [Salaf] preferred fasting to all other acts of worship; when questioned why, they replied, ‘For Allah to look upon me whilst my soul is challenging me concerning food and drink is more beloved to me than for Him to look upon me whilst it is challenging me concerning disobedience....’ 
20. Opportunity for being charitable and benevolent
‘...the fasting person experiences hunger so he comprehends the severity of the pain of hunger; this urges him to be benevolent to those who are without food. It also causes him to reflect on the harms of being powerless and isolated; as only one who is afflicted with a difficulty can really be aware of it...’ 
21. A gentle heart and safeguarded limbs
The Prophet said, ‘There will enter Paradise a people whose hearts are like the hearts of birds.’ 
Al-Qastalani lists as one of the benefits of fasting,
‘The gentleness of the heart and much weeping; and this is one of the causes of happiness. Eating one’s fill does away with the light of real knowledge and imposes harshness and disentitlement.’
He also lists,
‘Safeguarding the limbs from persisting in wrongdoings; this is one of the greatest benefits to fasting. In fact it lies at the foundation of fulfilling the purpose. If one’s soul is touched with the pain of hunger it becomes submissive and obedient and distracted with this circumstance from extending its aspirations towards vile thoughts and thus its limbs will cease from committing improper movements and will stop short of violating what is sacred. The limbs are seven: the eye, ear, tongue, stomach, private parts, hand and foot. The soul supports these limbs and is the considered root. If the root weakens the branches weaken likewise and this is the secret to fasting...’ 
3. al-Bukhari and Muslim.
4. al-Fath, vol. 4, pp 129-130.
5. al-Fath, vol.4, pg 130.
6. Fayd al-Qadir, vol.4, pg 251.
7. al-Fath, vol. 4, pg 130.
8. Al-Buhkari and Muslim.
9. Ibn Hibban in his al-Sahih and others.
10. al-Bayhaqi in Shu’ab al-Iman, Ahmad and al-Nasa’i.
11. al-Tabarani in al-Kabir, Ahmad and al-Nasa’i.
12. Ahmad, al-Nasa’i and Ibn Majah.
13. Fayd al-Qadir, vol.4, pg 242.
14. Related by al-Bazzar and declared hasan by al-Albani in Sahih al-Targhib, vol 1, pg 412.
15. Ahmad and others.
16. Ahmad in al-Zuhd.
18. Al-Bukhari and Muslim.
19. Mirqah al-Mafatih Sharh Mishkah al-Masabih.
20. Fawa’id al-Sawm.
21. Related by al-Bazzar and Ahmad. Refer to Sahih al-Jami’, number 6224.
22. Fayd al-Qadir, vol.6, pg 123.
23. Ahmad and al-Tabarani on al-Kabir.
24. al-Bayhaqi in Shu’ab al-Iman and others.
25. Ibn Hibban, Ahmad and others.
26. al-Tirmidhi and Ahmad.
27. Muslim and Ibn Hibban with his wording, and others.
28. Fayd al-Qadir
29. Madarik al-Maram fi Masalik al-Siyam
30. Fawai’d al-Sawm, pg. 25.
31. Madarik al-Maram, pg 76.
33. Madarik al-Maram, pp 79-80.