The Surah takes its name from the alphabetic letter Suad with which it begins.
As will be explained below, according to some traditions this Surah was sent down in the period when the Holy Prophet had started calling the people openly to Islam in Makkah, and this had caused great alarm among the chiefs of the Quraish. If this be true, its period of revelation would be about the 4th year of the Prophethood. According to some other traditions, it was sent down after Hadrat Umar's embracing Islam, and this happened, as is well known, after the migration to Habash. Another chain of the traditions shows that the event which occasioned the revelation of this Surah took place during the last illness of Abu Talib. If this be correct, the period of its revelation would be the 10th or 11th year of the Prophethood.
Here is a resume of the traditions related by Imam Ahmad, Nasa'i, Tirmidhi, Ibn Jarir, Ibn Abi Shaibah, Ibn Abu Hatim, Muhammad bin Ishaq and others:
When Abu Talib fell ill, and the Quraish chiefs knew that his end was near, they held consultations and decided to approach the old chief with the request that he should solve the dispute between them and his nephew. For they feared that if Abu Talib died and then they subjected Muhammad (upon whom be Allah's peace) to a harsh treatment, after his death, the Arabs would taunt them, saying, "They were afraid of the old chief as long as he lived now that he is dead they have started maltreating his nephew." At least 25 of the Quraish chiefs including Abu Jahl, Abu Sufyan, Umayyah bin Khalaf, As bin Wa'il, Aswad bin al-Muttalib, 'Uqbah bin Abi Mu'ait, Utbah and Shaibah went to Abu Talib. First, they put before him their complaints against the Holy Prophet as usual, then said, "We have come to present before you a just request and it is this : let your nephew leave us to our religion, and we shall leave him to his. He may worship whomever he may please: we shall not stand in his way in this matter; but he should not condemn our gods, and should not try to force us to give them up. Please tell him to make terms with us on this condition". Abu Talib called the Holy Prophet and said, "Dear nephew, these people of your tribe have come to me with a request. They want you to agree with them on a just matter so as to put an end to your dispute with them." Then he told him about the request of the chiefs of the Quraish. The Holy Prophet replied, "Dear uncle: I shall request them to agree upon a thing which, if they accept, will enable them to conquer the whole of Arabia and subject the non-Arab world to their domination. "Hearing this the people were first confounded; they did not know how they should turn down such a proposal. Then, after they had considered the matter, they replied: "You speak of one word: we are prepared to repeat ten others like it, but please tell us what it is." The Holy Prophet said: La ilaha ill-Allah. At this they got up all together and left the place saying what Allah has narrated in the initial part of this Surah.
Ibn Sa'd in his Tabaqat has related this event just as cited above, but, according to him, this did not happen during Abu Talibs last illness but at the time when the Holy Prophet had started preaching Islam openly, and the news of the conversion of one person or the other was being heard almost daily in Makkah. In those days the Quraish chiefs had led several deputations to Abu Talib and had asked him to stop Muhammad (upon whom be Allah's peace and blessings) from preaching his message, and it was with one of those deputations that this conversation had taken place.
Zamakhshari, Razi, Nisaburi ond some other commentators say that this deputation went to Abu Talib at the time then the chiefs of the Quraish had been upset at Hadrat Umar's embracing Islam; but no reference to its basis is available in any book of the traditions, nor have these commentators cited the source of their this information. However, if it be true, it is understand able. For the unbelieving Quraish had already been bewildered to see that the person who had arisen from among themselves with the message of Islam had no parallel in the entire tribe as regarded nobility, purity of character, wisdom and seriousness. Moreover, his right hand man and chief supporter was a man like Abu Bakr, who was well known in and around Makkah as a gentle, righteous and brilliant man. Now when they might have seen that a brave and resolute man like Umar also had joined them, they must have felt that the danger was growing and becoming intolerable.
The Surah begins with a review of the aforesaid meeting. Making the dialogue between the Holy Prophet and the disbelievers the basis, Allah says that the actual reason with those people for their denial is not any defect in the message of Islam but their own arrogance, jealousy and insistence on following the blind. They are not prepared to believe in a man from their own clan as a Prophet of God and follow him. They want to persist in the ideas of ignorance which they have found their ancestors following. And when a person exposes their this ignorance and presents the truth before them, they are alarmed and regard it as an oddity, rather as a novel and impossible thing. For them the concept of Tauhid and the Hereafter is not only an unacceptable creed but also a concept which only deserves to be ridiculed and mocked.
Then, Allah, both in the initial part of the Surah and in its last sentences, has precisely warned the disbelievers, as if to say, "The man whom you are ridiculing today and whose guidance you reject will soon overpower you,and the time is not far when in this very city of Makkah, where you are persecuting him, he will overwhelm you completely."
Then describing nine of the Prophets, one after the other, with greater details of the story of the Prophets David and Solomon; Allah has emphasized the point that His Law of Justice is impartial and objective, that only the right attitude of man is acceptable to Him, that He calls to account and punishes every wrongdoer who. ever he be, and that He likes only those people who do not persist in wrongdoing but repent as soon as they are warned of it, and pass their life in the world keeping in mind their accountability in the Hereafter.
After this, the final end that the obedient servants and the disobedient people will meet in the Hereafter, has been depicted, and two things have been especially impressed on the disbelievers:(1) That the leaders and guides whom the ignorant people are following blindly in the world, on the way of deviation, will have reached Hell even before their followers in the Hereafter, and the two groups will be cursing each other there; and (2) that the disbelievers will be amazed to see that there is no trace whatever in Hell of the believers whom they used to regard as contemptible in the world and will themselves be involved in its torment.
In conclusion, mention has been made of the story of Adam and Iblis (Satan), which is meant to tell the disbelieving Quraish that the same arrogance and vanity which was preventing them from bowing before Muhammad (upon whom be Allah's peace) had prevented Iblis also from bowing before Adam. Iblis felt jealous of the high rank God had given to Adam and became accursed when he disobeyed His Command. Likewise, "You, O people of Quraish, are feeling jealous of the high rank God has bestowed on Muhammad (upon whom be Allah's peace) and are not prepared to obey him whom God has appointed His messenger. Therefore, you will be doomed ultimately to the same fate as will be met by Satan."
Source: Sayyid Abul Ala Maududi - Tafhim al-Qur'an - The Meaning of the Quran