Allah tells us that when man is in dire straits, he calls upon Allah alone with no partner or associate, then when times of ease come and they have the choice, some people associate others with Allah and worship others alongside Him.

لِيَكْفُرُواْ بِمَآ ءاتَيْنَـهُمْ

(So as to be ungrateful for the graces which We have bestowed on them.) Then Allah warns them by saying:

فَسَوْفَ تَعْلَمُونَ

(but you will come to know.) One of them said: By Allah, if a law enforcment officer were to say this to me, I would be afraid, so how about when the One Who is issuing the warning is the One Who merely says to a thing "Be!" and it is Then Allah denounces the idolators for fabricating lies and worshipping others instead of Him with no evidence or proof:

أَمْ أَنزَلْنَا عَلَيْهِمْ سُلْطَـناً

(Or have We revealed to them an authority,) means, proof.

فَهُوَ يَتَكَلَّمُ

(which speaks) means, tells

بِمَا كَانُواْ بِهِ يُشْرِكُونَ

(of that which they have been associating with Him) This is a rhetorical question intended to denounce them, for they have no such thing.

وَإِذَآ أَذَقْنَا النَّاسَ رَحْمَةً فَرِحُواْ بِهَا وَإِن تُصِبْهُمْ سَيِّئَةٌ بِمَا قَدَّمَتْ أَيْدِيهِمْ إِذَا هُمْ يَقْنَطُونَ

(And when We cause mankind to taste of mercy, they rejoice therein; but when some evil afflicts them because of what their hands have sent forth, behold, they are in despair!) This is a denunciation of man for the way he is, except for those whom Allah protects and helps, for when man is given blessings, he is proud, and says:

ذَهَبَ السَّيِّئَاتُ عَنِّي إِنَّهُ لَفَرِحٌ فَخُورٌ

("Ills have departed from me." Surely, he is exultant, and boastful.) (11:10) He rejoices over himself and boasts to others, but when difficulties befall him, He despairs of ever having anything good again. Allah says:

إِلاَّ الَّذِينَ صَبَرُواْ وَعَمِلُواْ الصَّـلِحَاتِ

(Except those who show patience and do righteous good deeds). They are patient during times of difficulty and do good deeds at times of ease. It was reported in the Sahih:

«عَجَبًا لِلْمُؤْمِنِ لَا يَقْضِي اللهُ لَهُ قَضَاءً إِلَّا كَانَ خَيْرًا لَهُ، إِنْ أَصَابَتْهُ سَرَّاءُ شَكَرَ فَكَانَ خَيْرًا لَهُ، وَإِنْ أَصَابَتْهُ ضَرَّاءُ صَبَرَ فَكَانَ خَيْرًا لَه»

(How wonderful is the affair of the believer. Allah does not decree anything for him but it is good for him. If good things happen to him, he gives thanks, and that is good for him; and if bad things happen to him, he bears that with patience, and that is good for him.)

أَوَلَمْ يَرَوْاْ أَنَّ اللَّهَ يَبْسُطُ الرِّزْقَ لِمَن يَشَآءُ وَيَقْدِرُ

(Do they not see that Allah expands the provision for whom He wills and straitens (it for whom He wills).) He is the One Who is controlling and doing that, by His wisdom and justice, so He expands the provision for some people and restricts it for some.

إِنَّ فِى ذلِكَ لآيَـتٍ لِّقَوْمٍ يُؤْمِنُونَ

(Verily, in that are indeed signs for a people who believe.)