The goal of this Surah is to elucidate upon a series of life-giving commandments of Akhlaq (Ethics and Morality) and social interaction which (if put into practice), would lead an ideal civilization. These in turn could create and cultivate a pure society that is far removed from all sorts of blameworthy moral traits.
According to the unanimous verdict of all the commentators of the Qur’an, the number of verses of this Surah are eighteen. Through its own particular way of explaining things, this Surah incorporates a series of comprehensive and beneficial commandments for the purification of the soul and spirit for all of humanity. If the conditions and ethical injunctions mentioned in this Surah were acted upon within all societies, then we would definitely be able to bring about a calm and peaceful environment full of consideration (for others) and contentment for all – far removed from all sorts of wicked and evil ethical traits.
This Surah gives us an overall view of a pure and uncontaminated society in which not only the tongue and ears of the individuals, rather even their thoughts and reflections are not given complete free reign, such that are free to say whatever they want to say, hear whatever they want to hear, or do whatever they wish to do in relation to other people.
The following is a list summarizing the commandments that are mentioned in this Surah:
1. This Surah begins its first commandment by bringing up a point in regards to having discipline and order, while in the presence of Allah (Glorified and Exalted is He) and the Messenger (blessings of Allah be upon him and his progeny). The meaning of this discipline and order is that the Muslims must learn the commandments and legislations (of the religion) from Allah (Glorified and Exalted is He) and must not let their own inner desires and whims lead them to formulating laws and regulations.
2. The people who have true faith are instructed and commanded how they should speak to their leaders.
3. The people who have true faith are also commanded that when they are given news or testimony about another person from one who commits sins in the open, is known for his wicked ways or is not scared of his transgressions (against the laws of Allah, Glorified and Exalted is He), that they must not accept such a testimony from him and must stay away from all forms of rumours and gossip.
4. The general thoughts and opinions of the people have absolutely no value when compared to the orders and directives of the infallible Prophet (blessings of Allah be upon him and his progeny).
5. Each and every person possesses an ethical conscience.
6. It is incumbent upon every Muslim that he strives for peace, and to attain this goal he must stand up against the oppressors so that he would be able to uphold the truth and maintain the rights of the oppressed.
7. All Muslims are brothers (and sisters) of and equal to one another and it is incumbent that they all endeavour to ensure that peace and happiness are established amongst themselves.
8. A Muslim does not have the right to make fun of another Muslim.
9. It is forbidden to find or pick faults in other people according to the teachings of Islam.
10. A true believer does not have the right to call his brother in faith by a nickname or bad name.
11. It is forbidden (haram) to think bad thoughts about a believing brother (or sister).
12. It is expressly forbidden to spy on or pry into the secrets and private life and affairs of other people.
13. It is a major sin to speak bad things behind the back of another Muslim.
14. In this Surah, the issue of racial superiority has also been brought to an end and the only criteria for judging who is better (than another person) is one’s merit, piety and abstinence from those things which Allah (Glorified and Exalted is He) has forbidden and by keeping away from all sins.
After these fourteen commandments have been explained, there is another series of issues that are discussed which will be explained in their own section. When glancing over these commandments, is the superiority and dominance of the ethical Qur’anic teachings over all other ethical teachings of the world not clear and obvious for all to see?

This Surah was Revealed in Madinah, Not Makkah
We are able to discern which Surahs were revealed in Makkah and which were revealed in Madinah by keeping the following two points in mind:
1. The narrations and traditions which mention to us the place of revelation of a specific Surah.
2. Pondering and thinking over the contents of the verses of the Surah which usually act as a verbal chain of events that tell us if the Surah was revealed in Makkah or Madinah.
Seeing as how the cities of Makkah and Madinah were two completely different environments, we understand that each was governed by its own ways of thought, and thus the religion of Islam was put face to face with issues and difficulties which were specific to that particular area.
Thus, after we are acquainted with the way of thinking and the particular issues of an area (Makkah or Madinah), and we have studied the contents and verses of a Surah, then we are then able to discern where the Surah or the verses of the Surah were revealed.
For instance, the environment of Makkah was one polluted with polytheism and idol worship. The Jews and Christians had not permeated into this city and thus, those who had true faith (Iman) were very small in number. The issue of Jihad and fighting were not brought up in this environment and the Prophet (blessings of Allah be upon him and his progeny) had frequent dealings and relations with the idol worshippers.
Therefore, the point of difference of the Prophet (blessings of Allah be upon him and his progeny) with the polytheists (of Makkah) was concerning Tawhid (the Oneness of Allah, Glorified and Exalted is He) and the concept of being brought back to life on the Day of Judgement after one was physically dead.
Thus, the verses whose axis rotates around the discussion of issues such as the origin (of life), Resurrection Day and the verses which reproach Polytheism and speak about the outcome of the previous generations that were inflicted with the anger and punishment of Allah (Glorified and Exalted is He) due to not following His commandments and their appointed Messengers, were most often revealed in Makkah.
However the environment in Madinah was an atmosphere of faith, virtue and piety. It was a centred where the Ahl al-Kitab - especially the Jews – had influenced and permeated into. It was an atmosphere of young men, heroes, champions and brave people who readily accepted the teachings of Islam.
In addition, it was also an environment where the Muslims had little need to discuss the foundational beliefs (Usul ad-Din) of the religion and thus it was time for them to become acquainted with a series of other issues including their practical responsibilities, the ethical and societal guidelines and the performance of devotional acts such as Salat, Sawm (fasting), Zakat and other issues.
It is because of this fact that the verses in relation to the Tawrat and Injil and the beliefs of the Ahl al-Kitab (Jews and Christians) and the explanation of the altercations, battles and wars of the Muslims with the Ahl al-Kitab and the Polytheists were revealed in Madinah.
Also, the verses that speak of the principles of etiquette and the commandments of the religion including the obligatory (wajib) and recommended (mustahab) acts were all revealed in Madinah – meaning after the migration (hijrah) of the Prophet (blessings of Allah be upon him and his progeny) from Makkah to Madinah.[1]
Given that the mood in Madinah was one of interaction between the Prophet (blessings of Allah be upon him and his progeny) and the Ansar (the local people of Madinah who welcomed the Prophet and his followers to their city) and other groups that slowly accepted the teachings of Islam, this limited time frame did not permit the Prophet (blessings of Allah be upon him and his progeny) to discuss issues such as condemning idols and idol worshippers (while in Madinah). Therefore we must acknowledge that all the verses of this Surah were revealed in Madinah.
In addition to all of the commentators of the Qur’an being unanimous on this issue (that all of the verses of this Surah were revealed in Madinah) – and it has only been related from Ibn `Abbas that in his opinion, the thirteenth verse of this Surah was revealed in Makkah – the contents of these verses are a living, practical example that they were all revealed in Madinah.
The atmosphere in Makkah was not conducive to discussing these sorts of ethical issues, since the people of Makkah still held doubts concerning the principles of Islam (origin of life and Day of Resurrection), and did not attest to the prophetic mission of the Prophet of Islam (blessings of Allah be upon him and his progeny) and had not yet developed faith in his universal message.
In such an environment, the opportunity never arose that would allow the Prophet (blessings of Allah be upon him and his progeny) to bring up issues of morality such as having bad thoughts about others or backbiting other people.
Above all of this, those who are being spoken to in this Surah are those that possess true faith (Mu’minun), just as we see that Allah (Glorified and Exalted is He) has started out this Surah with the phrase:

يٌا أَيُّهٌا الَّذِينَ آمَنُوا

{O’ you who have true faith!}
Thus, from this beginning of this Surah until we reach the end, we see that with the exception of one instance, all of the contents of this chapter are addressed to the believers or those who have true faith and this is one indisputable indication that this Surah was revealed in Madinah.

Notes:
[1] Those verses which were revealed to the Prophet (blessings of Allah be upon him and his progeny) during his Hajjatul Wida` or Farewell Hajj (before he passed away) while in Makkah are technically referred to as Madani verses (verses revealed in Madinah) of the Qur’an even though they were not actually sent to him in the city of Madinah. This is so because the condition that is used to judge whether a verse is Madani is if it was revealed after the migration to Madinah. It is by observing this definition that we have given the above classification (in relation to the place of revelation).