1. Ar-Rayyan Gate is for those who observes Saum (sincerely). Narrated Sahl ibn Sa’d (radiallah ‘anhu) the Prophet (sallallaahu ‘alaihi wa sallam) said:
“There is a gate in Paradise called Ar-Rayyan, and those who observe Saum (fast) will enter through it on the Day of Resurrection and none except them will enter through it. It will be said: ‘Where are those who observed Saum.’ They will get up, and none except them will enter through it. After they have entered, the gate will be closed and nobody will enter it.” (Bukhari and Muslim)
Narrated Abu Hurairah (radiallah ‘anhu), Allah’s Messenger (sallallaahu ‘alaihi wa sallam) said:
“Whoever gives two kinds (of things or properties) in charity for Allah’s Cause, and whoever was amongst those who used to observe Saum will be called from the gate of Ar-Rayyan.” (Bukhari)
2. Observing Saum restricts sexual desire. Narrated Abdullah ibn Mas’ood (radiallah ‘anhu),  the Prophet (sallallaahu ‘alaihi wa sallam) said:
“O young men! He who can afford marriage expenses should get married, and he who cannot afford to marry is advised to observe Saum, as As-Saum will diminish his sexual power.” (Bukhari and others)
3. There are two pleasures for the person observing Saum; when he breaks the fast and when he meets his Rabb.
4. The doubling for many times the rewards of the one who observes Saum to an extent not known except by Allah (subhanahu wa ta’ala).
5. The smell coming out from the mouth of the person observing Saum is better in the sight of Allah (subhanahu wa ta’ala) than the smell of musk.
Narrated Abu Hurairah (radiallah ‘anhu), the Prophet (sallallaahu ‘alaihi wa sallam) said:
“All the deeds of Adam’s sons (people) are for them; the reward (of their good deeds) will be multiplied ten times to seven hundred times. Allah said: ‘Except As-Saum which is for Me and I will reward for it. He [ie the one who observes Saum] leaves his [sexual] desire and food for Me [ie My Pleasure]’. There are two pleasures for the person observing Saum; one at the time of Iftar (breaking his Saum) and the other at the time when he will meet his Rabb. Verily, the smell coming out from the mouth of the person observing Saum is better in Allah’s sight than the smell of musk.” (Bukhari, Muslim and others).
6. As-Saum is a shield. Narrated Abu Hurairah (radiallah ‘anhu), the Prophet (sallallaahu ‘alaihi wa sallam) said:
“As-Saum is a shield (or a screen or a shelter from the Hell-fire). So, the person observing Saum should avoid sexual relation with his wife and should not behave foolishly and impudently. And if somebody fights with him or abuses him, he should say to him twice, ‘I am observing Saum’. By Him in Whose Hand is my soul, the smell coming out from the mouth of the person observing Saum is better in Allah’s sight  than the smell of musk. [Allah (subhanahu wa ta’ala) says about the person observing Saum] ‘He has left his food, drink and desires for My Sake. The Saum is for his food, drink and desires for My Sake. The Saum is for Me. So, I will reward (the person observing Saum) for it and the reward of good deeds is multiplied ten times.” (Bukhari)
Narrated Abu Sa’id (radiallah ‘anhu), the Prophet (sallallaahu ‘alaihi wa sallam) said:
“No Muslim fasts one day for the sake of Allah but Allah will take his face far away from Hell-fire the distance of 70 autumns.” (Bukhari and Muslim).
7. Saum expiates sins. Narrated Huthaifah (radiallah ‘anhu), the Prophet (sallallaahu ‘alaihi wa sallam) said:
“…sins one commits concerning his household (family), or wealth are expiated by performing Salah – prayers, observing Saum and giving charities.” (Bukhari, Muslim and others. This is a part of a long hadith).
(Taken from Aqil ibn Zaid al-Maqtiri’s book Fasting Rules)


Mistakes made in Suhoor (predawn meal)
Some of the mistakes that fasting people make in regard to Suhoor are:
1-Some people do not have Suhoor and this is contrary to the Sunnah. It is from the guidance of the Prophet, sallallaahu ‘alaihi wa sallam, to have Suhoor if the person intends to observe obligatory or voluntary fasting. Urging Muslims to have Suhoor. The Prophet, sallallaahu ‘alaihi wa sallam, said:
“Have Suhoor, as indeed there is a blessing in it.” [Al-Bukhari and Muslim] 
“The difference between our fasting and the fasting of the People of the Book is the (meal of) Suhoor.” [Muslim] 
Moreover, Suhoor helps the Muslim to fast, and it is a blessed act of the Sunnah, so it should not be overlooked.
2- Having Suhoor early in the middle of the night or one or two hours before dawn is also contrary to the Sunnah. The Prophet, sallallaahu ‘alaihi wa sallam, said: “Hasten to (eating) Iftaar (in Ramadan immediately when the time is due), and delay (eating) Suhoor.” [At-Tabaraani] It is an act of the Sunnah to have Suhoor just before dawn (about half an hour before it). Anas, May Allah be pleased with him, he said: “The Prophet, sallallaahu ‘alaihi wa sallam, and Zayd ibn Thaabit, may Allah be pleased with him, had Suhoor. When they finished, the Prophet, sallallaahu ‘alaihi wa sallam, left for the prayer. Anas, may Allaah be pleased with him, was asked how much time was there between their finishing Suhoor and entering the prayer; he said: ‘Enough time for the recitation of 50 verses (of the Qur’an).’” [Al-Bukhari]
3- Continuing to eat (Suhoor) even after hearing the Fajr prayer Athaan. Out of prudence for one’s fasting, one should stop having his Suhoor two or three minutes before or at most when he hears the Athaan for Fajr.
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