Name of Chapter and Reason for its Name
The name of this chapter is Surah al-Maun, and the name has been taken from its last verse.
Surah al-Maun is the 107th chapter of the Quran.
Number of Verses
Place of Revelation
Even though it has been propounded that this chapter has the potential to be both Makki and Madani,  some commentators consider this chapter to be potentially Makki.   Some commentators say that the first three verses are Makki, while the remainder of the verses are Madani. 
Important Concepts in this Chapter
A reference and explanation is made about the characteristics of the deniers. Ruyat is defined as seeing with the physical eyes, or insight and deep recognition.  The characteristics of the deniers in these verses are those who reject the orphans with force and oppression, as well as not having an inclination towards feeding the destitute.   By using the syntax of the words ‘Ta am al-Miskeen’ in verse 2 - ?the feeding of the destitute can be taken as a reminder of the ownership of the destitute with regard to feeding. 
A reference is made to those who take the prayers lightly and an explanation of their characteristics.
Verse 5 which states: “…but are heedless of their prayers” means those who are heedless of their prayers or those who take it lightly, or it is in relation to those who do not display feeling towards the lapse of the time of prayer, or those who pray sometimes on certain occasions, or those who delay their prayers after the time sets in.   It also refers to those who pray in the public eye, but in private they miss their prayers. 
Verse 6 says: “—who show off” means those who worship so that people may see them, and this is one of the characteristics of those who are careless about their prayers. 
The word Maun means financial aid to others such as loans, donations, and lending money,  or it has also been said that the intended meaning of Maun is zakah which is obligatory [to pay] on wealth.  
Controversial Verses in this Chapter
As a footnote to verse 5, “but are heedless of their prayers” a discussion regarding whether the Prophet can make a mistake in his prayers has been propounded - and this is an important theological discussion. If the difference between ‘heedless of their prayers’ and ‘heedless in their prayers’ is understood, then in the former case it is related to taking one’s prayers lightly, and in the latter case it is a reference to mistakes which one makes in the prayers which occurs due to the whisperings of Satan. Some people believe that the Prophet was affected by a mistake by which is meant forgetfulness. 
Discussions on this Chapter
According to the Sunni Traditions
Benefits of Reciting this Surah
عن رسول اللّه صلى اللّه عليه و سلم: من قرأ سورة أ رأيت غفر اللّه له إن كان للزكاة مؤديا
The Prophet of Allah has said: “A person who recites Surah [al-Maun], Allah will forgive for him [the amount of] any zakah which he contributed.” 
Verse 5: “Those who are heedless of their prayers,”
ٱلَّذِينَ هُمۡ عَن صَلَاتِهِمۡ سَاهُونَ ٥ ثبت في الصحيحين أن رسول اللّه صلّى اللّه عليه و سلّم قال: تلك صلاة المنافق، تلك صلاة المنافق، تلك صلاة المنافق، يجلس يرقب الشمس حتى إذا كانت بين قرني الشيطان قام فنقر أربعا لا يذكر اللّه فيها إلا قليلا
It is established from the two correct [sources] that the Prophet of Allah said: “This is the prayer of the hypocrite, this is the prayer of the hypocrite, this is the prayer of the hypocrite. He sits watching the sun until it is between the two horns of Satan, then he stands and pecks four (rakat) and he does not remember Allah (in them) except very little.” 
عن سعد بن أبي وقاص قال: سألت رسول اللّه صلّى اللّه عليه و سلّم عن الَّذِينَ هُمْ عَنْ صَلاتِهِمْ ساهُونَ قال: هم الذين يؤخرون الصلاة عن وقتها
It has been narrated from Sad ibn Abu Waqqas who said: “I asked the Prophet of Allah regarding the verse ‘...heedless of their prayers…’ and he said, ‘They are those who delay the time of their prayers.’” 
Verse 6: “Those who show off.”
ٱلَّذِينَ هُمۡ يُرَآءُونَ ٦ عن ابن عباس رضي اللّه عنهما عن النبي صلّى اللّه عليه و سلّم قال: إن في جهنم لواديا تستعيذ جهنم من ذلك الوادي في كل يوم أربعمائة مرة أعد ذلك للمرائين من أمة محمد لحامل كتاب اللّه و للمصدق في غير ذات اللّه و للحاج إلى بيت اللّه و للخارج في سبيل اللّه
Ibn Abbas narrates from the Prophet who said: “Surely in Hell there is a valley from which even Hell seeks protection. In this valley, every day 400 times, it prepares hypocrites from the nation of Muhammad bearing the Book of Allah… and the visitors to the House of Allah and those outside of Allah’s path.” 
According to the Shia Traditions
Benefits of Reciting this Surah (all references are exact same here)
عَمْرِو بْنِ ثَابِتٍ عَنْ أَبِي جَعْفَرٍ قَالَ مَنْ قَرَأَ أَ رَأَيْتَ الَّذِي يُكَذِّبُ بِالدِّينِ فِي فَرَائِضِهِ وَ نَوَافِلِهِ قَبِلَ اللَّهُ صَلَاتَهُ وَ صِيَامَهُ وَ لَمْ يُحَاسِبْهُ بِمَا كَانَ مِنْهُ فِي الْحَيَاةِ الدُّنْيَا
Umar ibn Thabit quotes Abu Jafar who said: “Whoever recites [this chapter] in his faraidah (daily obligatory prayers) and his nawafilah (recommended prayers), Allah will accept his prayers and fasts, and will not hold him accountable for that which was from him in the material world.” 
Verse 5: “Those who are heedless of their prayers.”
ٱلَّذِينَ هُمۡ عَن صَلَاتِهِمۡ سَاهُونَ ٥ عَنْ يُونُس بْنِ عَمَّارٍ عَنْ أَبِي عَبْدِ اللَّهِ قَالَ سَأَلْتُهُ عَنْ قَوْلِهِ « الَّذِينَ هُمْ عَنْ صَلاتِهِمْ ساهُونَ » أَ هِيَ وَسْوَسَةُ الشَّيْطَانِ فَقَالَ لَا كُلُّ أَحَدٍ يُصِيبُهُ هَذَا وَ لَكِنْ أَنْ يُغْفِلَهَا وَ يَدَع أَنْ يُصَلِّيَ فِي أَوَّلِ وَقْتِهَا.
Yunus ibn Ammar narrates from Abu Abdillah who said: “I asked him regarding [this verse], ‘Is it the whisperings of Satan?’ to which he replied, ‘No one has been afflicted by this unless he was heedless of it, and called towards reciting the prayers at the beginning of its time.’” 
عَنْ أَبِي أُسَامَة زَيْد الشَّحَّامِ قَالَ سَأَلْتُ أَبَا عَبْدِ اللَّهِ عَنْ قَوْلِ اللَّهِ « الَّذِينَ هُمْ عَنْ صَلاتِهِمْ ساهُونَ » قَالَ هُوَ التَّرْكُ لَهَا وَ التَّوَانِي عَنْهَا.
Abu Usama Zayd al-Shahham says that: “I asked Abu Abdillah regarding Allah’s words [in this verse], to which he replied, ‘[It is regarding] one who abandons it (the prayers) and shows indifference towards it.’” 
عَنْ مُحَمَّدِ بْنِ الْفُضَيْلِ عَنْ أَبِي الْحَسَنِ قَالَ هُوَ التَّضْيِيعُ لها
Muhammad ibn Fudayl quotes Abul Hasan who said: “[It is regarding] one who squanders it (the prayers).” 
Verse 7: “But deny aid.”
وَيَمۡنَعُونَ ٱلۡمَاعُونَ ٧ فقيل هي الزَّكَاة الْمَفْرُوضَة عَنْ عَلِيٍّ وَ ابْن عُمَرَ وَ الْحَسَنُ وَ قَتَادَة وَ الضَّحَّاك وَ رُوِيَ ذَلِكَ عَنْ أَبِي عَبْدِ اللَّهِ
It is said that this is the imposed zakah, as has been narrated from Ali and Ibn Umar and Hasan and Qatadah and Dahhak and Abu Abdillah. 
رَوَى أَبُو بَصِيرٍ عَنْ أَبِي عَبْدِ اللَّهِ قَالَ هُوَ الْقَرْض تُقْرِضُهُ وَ الْمَعْرُوف تَصْنَعُهُ وَ مَتَاع الْبَيْتِ تُعِيرُهُ وَ مِنْهُ الزَّكَاةُ قَالَ فَقُلْتُ إِنَّ لَنَا جِيرَاناً إِذَا أَعرنَاهُمْ مَتَاعاً كَسَرُوهُ وَ أَفْسَدُوهُ أَ فَعَلَيْنَا جُنَاح أَنْ نَمْنَعَهُمْ فَقَالَ لَا لَيْسَ عَلَيْكَ جُنَاح أَنْ تَمْنَعَهُمْ إِذَا كَانُوا كَذَلِكَ
It has been narrated from Abu Baseer from Abu Abdillah who said: “This is an imposed loan and the property of the house which you lend, and from it is zakah.” Then I said: “Surely we have neighbors that when we lend to them, they break it and corrupt it - so is there any misdemeanor for forbidding them?” Then he replied: “There is no misdemeanor upon you if you forbid them if it is as such.”  This next part is all about the ayah #5, but here it talks about ayah #7???
فِي الْخِصَالِ ، عَنْ عَلِيٍّ فِي حَدِيثِ الْأَرْبَعِمِائَةِ قَالَ : لَيْسَ عَمَل أَحَبَّ إِلَى اللَّهِ عَزَّ وَ جَلَّ مِنَ الصَّلَاةِ - فَلَا يَشْغَلَنَّكُمْ عَنْ أَوْقَاتِهَا شَيْء مِنْ أُمُورِ الدُّنْيَا - فَإِنَّ اللَّهَ عَزَّ وَ جَلَّ ذَمَّ أَقْوَاماً فَقَالَ : « الَّذِينَ هُمْ عَنْ صَلاتِهِمْ ساهُونَ » يَعْنِي أَنَّهُمْ غَافِلُونَ اسْتَهَانُوا بِأَوْقَاتِهَا.
In the book Al-Khisaal, it has been narrated from Ali in the 400 narrations that he said: “There is no action more beloved to Allah, the Almighty than prayer – so do not occupy that time [of prayer] with the affairs of this world – for surely Allah, the Almighty has criticized those people when He says: “but are heedless of their prayers…” which means surely that they are heedless and consider unimportant [with regard] to its timings.” 
وَ فِي الْكَافِي ، بِإِسْنَادِهِ عَنْ مُحَمَّدِ بْنِ الْفُضَيْلِ قَالَ : سَأَلْتُ عَبْداً صَالِحاً عَنْ قَوْلِ اللَّهِ عَزَّ وَ جَلَّ : « الَّذِينَ هُمْ عَنْ صَلاتِهِمْ ساهُونَ » قَالَ هُوَ التَّضْيِيعُ.
In the book Al-Kafi, it has been narrated from the chain of Muhammad ibn al-Fudayl who said: “I asked a righteous servant regarding the verse of Allah, the Almighty, ‘but they are heedless of their prayers…’ to which he replied, ‘He is wasted.’” 
وَ فِي الدُّرِّ الْمَنْثُورِ ، أَخْرَجَ ابْنُ جَرِيرٍ وَ ابْنِ أَبِي حَاتِمٍ وَ الْبَيْهَقِيّ فِي سُنَنِهِ عَنْ عَلِيِّ بْنِ أَبِي طَالِبٍ « الَّذِينَ هُمْ يُراؤُنَ » قَالَ : يُرَاءُونَ بِصَلَاتِهِمْ.
From Al-Durr al-Manthur, in a narration which comes from Ibn Jarir and Ibn Abu Haatim and al-Bayhaqiyy from Ali ibn Abi Talib [who said regarding] “but they are heedless of their prayers” that: “They are heedless towards their prayers.” 
عَنْ أَبِي هُرَيْرَة عَنِ النَّبِيِّ ص فِي قَوْلِهِ « وَ يَمْنَعُونَ الْماعُونَ » قَالَ : مَا تَعَاوَنَ النَّاسُ بَيْنَهُمُ الفأس وَ الْقَدَرَ وَ الدَّلْوِ وَ أَشْبَاهِهِ
Abu Hurayrah quotes the Prophet on his words [regarding the verse] “but deny aid” that he said: “That which the people use for help between them and lend to each other, [such as] axes, pots, buckets and the like.” 
وَ فِي الْكَافِي ، بِإِسْنَادِهِ عَنْ أَبِي بَصِيرٍ عَنْ أَبِي عَبْدِ اللَّهِ فِي حَدِيثٍ قال و قَوْله عَزَّ وَ جَلَّ : « وَ يَمْنَعُونَ الْماعُونَ » هُوَ الْقَرْض تُقْرِضُهُ وَ الْمَعْرُوف تَصْنَعُهُ - وَ مَتَاعُ الْبَيْتِ تُعِيرُهُ وَ مِنْهُ الزَّكَاة
In Al-Kafi from the chain of narrators, Abu Baseer quotes Abu Abdillah as having said regarding the verse: ‘but deny aid’ that “It is a loan which is given, and is good that it is done, and it is the furniture of the house that you give as a loan, and zakah is one of the instances of it.” 
عَنْ عَلِيٍّ كَمَا فِي الدُّرِّ الْمَنْثُورِ ، وَ لَفْظُهُ : الْمَاعُونُ الزَّكَاةُ الْمَفْرُوضَة - يُرَاءُونَ بِصَلَاتِهِمْ وَ يَمْنَعُونَ زَكَاتهمْ
Al-Durr al-Manthur quotes Ali as having said that: “Maun is an obligatory zakah which they spare, and they show off and are hypocritical in their prayers, and they do not pay their zakah.” 
وَ فِي الدُّرِّ الْمَنْثُورِ ، أَخْرَجَ ابْنُ قَانِعٍ عَنْ عَلِيِّ بْنِ أَبِي طَالِبٍ قَالَ سَمِعْتُ رَسُولَ اللَّهِ ص يَقُولُ : الْمُسْلِمُ أَخُو الْمُسْلِمِ إِذَا لَقِيَهُ حَيَاة بِالسَّلَامِ - وَ يُرَدُّ عَلَيْهِ مَا هُوَ خَيْر مِنْهُ لَا يَمْنَعُ الْماعُونَ - قلت: يَا رَسُولَ اللَّهِ مَا الْماعُون ؟ قَالَ ( ص ) : الْحَجَرُ وَ الْحَدِيد وَ الْمَاءُ وَ أَشْبَاه ذَلِكَ
Also in Al-Durr al-Manthur, from Ibn Qaani who quotes from Ali ibn Abi Talib that: “I heard from the Prophet of Allah who said: ‘A Muslim is the brother of a Muslim, when he meets him he greets him with Salaam, and he returns that Salaam with one better than it. That is, he must say Salaam, and the other must reply and not prevent him from the Maun.’ I asked, ‘O Prophet, what is Maun?’ He replied, ‘[It is] rocks, iron, water and any other thing (which is a necessity).’” 
- Mahmud Zamakhshari, Al-Kashshaf an Haqa’iq Ghawamid al-Tanzil (1986), Volume 4, Page 803
- Sayyid Muhammad Husayn Tabatabai, Al-Mizan fi Tafsir al-Quran (1971), Volume 20, Page 367
- Fadhl ibn Hasan Tabrisi, Majma al-Bayan fi Tafsir al-Quran (1988), Volume 10, Page 832
- Tabatabai, Al-Mizan fi Tafsir al-Quran (1971), Page 367
- Ismail ibn Umar ibn Kathir Damishqi, Tafsir al-Quran al-Azim (1998), Volume 8, Page 467
- Tabrisi, Majma al-Bayan fi Tafsir al-Quran (1988), Page 832
- Zamakhshari, Al-Kashshaf an Haqaiq Ghawamid al-Tanzil (1986), Page 803
- Ibn Kathir Damishqi, Tafsir al-Quran al-Azim (1998), Page 467
- Zamakhshari, Al-Kashshaf an Haqaiq Ghawamid al-Tanzil (1986), Page 804
- Tabatabai, Al-Mizan fi Tafsir al-Quran (1971), Page 368
- Ibn Kathir Damishqi, Tafsir al-Qur’an al-Azim (1998), Page 468
- Tabatabai, Al-Mizan fi Tafsir al-Quran (1971), 368
- Tabrisi, Majma al-Bayan fi Tafsir al-Quran (1988), Page 834
- Ibid., Page 806
- Ibn Kathir Damishqi, Tafsir al-Quran al-Azim (1998), Page 468
- Ibid., Page 834
- Tabatabai, Al-Mizan fi Tafsir al-Quran (1972), Page 369