Allah said,

﴿وَإِذْ قَالُواْ اللَّهُمَّ إِن كَانَ هَـذَا هُوَ الْحَقَّ مِنْ عِندِكَ فَأَمْطِرْ عَلَيْنَا حِجَارَةً مِّنَ السَّمَآءِ أَوِ ائْتِنَا بِعَذَابٍ أَلِيمٍ ﴾

(And (remember) when they said: "O Allah! If this (the Qur'an) is indeed the truth (revealed) from You, then rain down stones on us from the sky or bring on us a painful torment.'')

This is indicative of the pagans' enormous ignorance, denial, stubbornness and transgression. They should have said, "O Allah! If this is the truth from You, then guide us to it and help us follow it.'' However, they brought Allah's judgment on themselves and asked for His punishment. Allah said in other Ayat,

﴿وَيَسْتَعْجِلُونَكَ بِالْعَذَابِ وَلَوْلاَ أَجَلٌ مُّسَمًّى لَّجَآءَهُمُ الْعَذَابُ وَلَيَأْتِيَنَّهُمْ بَغْتَةً وَهُمْ لاَ يَشْعُرُونَ ﴾

(And they ask you to hasten on the torment (for them), and had it not been for a term appointed, the torment would certainly have come to them. And surely, it will come upon them suddenly while they perceive not!) ﴿29:53﴾,

﴿وَقَالُواْ رَبَّنَا عَجِّل لَّنَا قِطَّنَا قَبْلَ يَوْمِ الْحِسَابِ ﴾

(They say: "Our Lord! Hasten to us Qittana (our record of good and bad deeds so that we may see it) before the Day of Reckoning!'') ﴿38:16﴾, and,

﴿سَأَلَ سَآئِلٌ بِعَذَابٍ وَاقِعٍ - لِّلْكَـفِرِينَ لَيْسَ لَهُ دَافِعٌ - مِّنَ اللَّهِ ذِي الْمَعَارِجِ ﴾

(A questioner asked concerning a torment about to befall. Upon the disbelievers, which none can avert. From Allah, the Lord of the ways of ascent.) ﴿70:1-3﴾

The ignorant ones in ancient times said similar things. The people of Shu`ayb said to him,

﴿فَأَسْقِطْ عَلَيْنَا كِسَفاً مِّنَ السَّمَآءِ إِن كُنتَ مِنَ الصَّـدِقِينَ ﴾

("So cause a piece of the heaven to fall on us, if you are of the truthful!'')﴿26:187﴾ while the pagans of Quraysh said,

﴿اللَّهُمَّ إِن كَانَ هَـذَا هُوَ الْحَقَّ مِنْ عِندِكَ فَأَمْطِرْ عَلَيْنَا حِجَارَةً مِّنَ السَّمَآءِ أَوِ ائْتِنَا بِعَذَابٍ أَلِيمٍ﴾

("O Allah! If this (the Qur'an) is indeed the truth (revealed) from You, then rain down stones on us from the sky or bring on us a painful torment.'')

Shu`bah said from `Abdul-Hamid that Anas bin Malik said that it was Abu Jahl bin Hisham who uttered this statement,

﴿اللَّهُمَّ إِن كَانَ هَـذَا هُوَ الْحَقَّ مِنْ عِندِكَ فَأَمْطِرْ عَلَيْنَا حِجَارَةً مِّنَ السَّمَآءِ أَوِ ائْتِنَا بِعَذَابٍ أَلِيمٍ﴾

("O Allah! If this (the Qur'an) is indeed the truth (revealed) from You, then rain down stones on us from the sky or bring on us a painful torment.'')

So Allah revealed this Ayah,

﴿وَمَا كَانَ اللَّهُ لِيُعَذِّبَهُمْ وَأَنتَ فِيهِمْ وَمَا كَانَ اللَّهُ مُعَذِّبَهُمْ وَهُمْ يَسْتَغْفِرُونَ ﴾

(And Allah would not punish them while you are among them, nor will He punish them while they seek (Allah's) forgiveness.)

Al-Bukhari recorded it.