The sura e Quraish descended at Mecca and it is consisted of 4 ayaat.

Surat Quraysh (Quraysh) - سورة قريش
The contents and virtues of Sura e Quraish
The sura e Quraish, infact it is taken into account and completes the sura e fil, its ayaat clearly proves this subject.
The contents of this sura define the divine blessings, kindness and comforts that the Almighty showered upon the tribe of Quraish to provoke their feelings of thankfulness and they began to worship the Benevolent God as they achieve the total exaltation and praise because of that great house of Kaaba
Same way in the beginning of the sura e vazzuha we defined that
Surat Az- Zuhaa' (The Morning Hours) - سورة الضحى
And the
Surat Ash-Sharh (The Relief) - سورة الشرح
the above two suras are considered as a single sura. The sura e fil and sura e Quraish become one sura together. If we go through its contents minutely they are so much connected together which can prove that they are alike.
About the virtues of reciting the sura e Quraish, it is enough to say that it is quoted from the prophet of Allah Muhammad peace be upon him who said: One who recites it, to number of persons who performed the circumambulation around the Kaaba or performed etekaf (to stay in seclusion in the place of worship and perform namaz and fasting for consequent days) there. Equal to each person who performed in the Kaaba ten good deeds will be given to him.
Certainly these virtues are for the persons who bow down before the Merciful God who is the protector of Kaaba and worship him. And guard the sanctity of this house and follow his message whole heartedly and practice upon it.

بسم الله الرحمن الرحیم

Sura e Quraish

لِإِيلَافِ قُرَيْشٍ
(106:1)

So That the Quraysh might remain secure,

إِيلَافِهِمْ رِحْلَةَ الشِّتَاء وَالصَّيْفِ
(106:2)

Their protection during their trading caravans in the winter and the summer-

فَلْيَعْبُدُوا رَبَّ هَذَا الْبَيْتِ
(106:3)

So let them worship (Allah) the Lord of this House (the Ka'bah in Makkah).

الَّذِي أَطْعَمَهُم مِّن جُوعٍ وَآمَنَهُم مِّنْ خَوْفٍ
(106:4)

Who has given them food against hunger, and made them safe from danger.

Definition
O provider god this house must be worshiped
As the previous sura a fil defined, regarding the destruction of the elephant army of Abraha who raided with a determination to terminate the house of Kaaba and to disperse this holy divine centre. The first ayat of this sura which in fact completes the sura e fil said: we destroyed like a crushed straw and dispersed the elephant army so that the people get familiar to this holy place. And get prepared for the introductions of the prophet Muhammad’s peace be upon him advent.

لِإِيلَافِ قُرَيْشٍ

إِيلَافِ
The above term means to get attached; it is taken from the word ulfath that is to get attached and to heal.
Any way the affection created between the holy house of Kaaba and the people of Mecca, the entire inhabitants of Mecca residing there, because of its central position, peace and tranquillity was prevailing in that territory. Most of the people of Hijaz (Arabia) were visiting Mecca every year to perform the haj pilgrimage. They were exchanging their literature and commodities as well through trade and enjoying the varied blessings of that land.
All these were occurring under the shadow of its specific peace and harmony and in the case if it had been destroyed by the military expedition of the Abraha and the invaders like him no body would had been got attachment to that place.

قُرَيْشٍ
This word Quraish, as most of the interpreters and the master of the dictionaries define it, actually this name belongs to a kind of aquatic animal who eats the other animal very conveniently. This phrase is famous from Ibn Abbas when it is asked: why the Quraish are named Quraish? He replied: This name is acquired by the biggest aquatic animal as it passes by any animal, lean or overweight, it engulfs them.
Therefore this name is selected for this tribe for their power and strength and they were misusing this power.

قرش
Some said: the above term gives the meaning of earning as the tribe of Quraish were engaged in the business deals and making money.
Several supposed: the above term means to investigate and enquire as the tribe of Quraish was always asking about the needs of pilgrims visiting kaaba and often trying to help them.
This term means to gather as well because this tribe was specifically involved in the assembling in solidarity. May be this name was selected for them.
But today the name Quraish never represents and motivates an attractive significance. In spite of the prophet belonging to that tribe, they were considered as the head strong enemies of the Islam. They were not leaving a single opportunity to obstruct and blockade the Muslims. Even when their power was shattered by the victory of Islam and they continued their secret planning against Islam which the history of Islam will never forget it. We are aware that Bani Umayya and Bani Abbas are the most prominent examples of the tyrannical and extreme devilish governments; they were upraised from the tribe of Quraish.
The evidence too shows that in the ignorant period of Arab, they too were constantly engaged in exploitation and misuse of the poor people’s hard earned money. For this reason as the freedom providing Islam rose up and their illegal earnings faced the risk of down fall and crumbled down and they stood up to fight against it but finally the great and the vital power of Islam crushed down them.
Next it adds: the purpose was that the Almighty God created the attachment in the hearts of Quraish in the summer and winter travelling.

إِيلَافِهِمْ رِحْلَةَ الشِّتَاء وَالصَّيْفِ

Possibly it means to make them attached and devoted to this holy land even during their summer and winter journey and must not remove from their heart its love and dedication. And to return there back for its peace and amity and do not get impressed by the comforts of the Yemen and Syria and vacate the Mecca city.
By creating attachment between Quraish and other tribes during their travelling, it has a deep meaning. As after the event of Abraha the people around them were looking upon them by another view and began to give importance, peace and amenity to Quraish.
Quraish tribe too was needed this harmony throughout their highways as well as in the city of Mecca, the Merciful God in the shadow of the defeat of the elephant’s army, provided for them peace both in the Mecca and its highways around.
We are aware that the land of Mecca does not have any field of agriculture or an orchard. Their occupation of animal husbandry too was very inadequate. Most of their income was provided by means of these commercial trading caravans.
In the winter season they were moving towards the south, the lands of Yemen which were comparatively warm. And in the summer season they were travelling towards north and the land of Syria which was possessing mild and favourable weather. In those days the dominions of Syria and Yemen were the important business centres, Mecca and Medina were being considered as a connecting link between them.
Of course due to the misdeeds committed by the Quraish they did not deserved such divine kindness and favour. But as it was predestined that among the tribe of Quraish and from that holy place, the prophet of Islam was going to rise up, the Sublime God showered this benevolence upon them.
In the next ayat it brings forth the result in such a manner that Quraish achieved that abundant divine kindness by the blessings of Kaaba. They must worship the Provider God of this house not the idols installed in it.

فَلْيَعْبُدُوا رَبَّ هَذَا الْبَيْتِ

The Generous God who saved them from the hunger and afforded them food and protected them from insecurity and provided them peace.

الَّذِي أَطْعَمَهُم مِّن جُوعٍ وَآمَنَهُم مِّنْ خَوْفٍ

From one side the Sovereign Lord made available for them the splendour business transaction and poured upon them the benefits. From other side the Majestic God warded off insecurity and repelled their losses. And all these blessings were obtained by the failure of the Abraha’s army.
In fact the acceptance of the prophet Ibrahim’s prayers before Allah established the foundation of the kaaba. But without paying any value to all that godly blessings, the people of Quraish transformed this holy house into the idols temple. They preferred to worship idols and left aside the prostration before the Almighty Allah. And at last these people came across the result of their entire inauspicious thanklessness.
O the guardian of faith, God: bless us with your kindness the capability to worship, serve you and express thanks to you, for your blessings grant to us the ability to guard this great house.
O the Supreme God: Day by day endow more magnificence to this great Islamic centre which links the entire connection for the Muslims of the world.
O the mighty Protector God: Ward off the evil hands from the holy centre who wants to misuse it.
Ameen O Provider of the universe