Tafsir Ibn Kathir (abridged)
Al-Hijr was revealed in Makkah
بِسْمِ اللَّهِ الرَّحْمَـنِ الرَّحِيمِ
In the Name of Allah, the Most Gracious, the Most Merciful.
The Disbelievers will someday wish that They had been Muslims
We have already discussed the letters which appear at the beginning of some Surahs. Allah said:
رُّبَمَا يَوَدُّ الَّذِينَ كَفَرُواْ
(How much would those who disbelieved wish) Here Allah tells us that they will regret having lived in disbelief, and will wish that they had been Muslims in this world. Regarding Allah's saying,
رُّبَمَا يَوَدُّ الَّذِينَ كَفَرُواْ لَوْ كَانُواْ مُسْلِمِينَ
(How much would those who disbelieved wish that they had been Muslims.) Sufyan Ath-Thawri reported from Salamah bin Kuhayl, who reported from Abi Az-Za`ra', from `Abdullah, who said: "This is about the Jahannamiyyun (the sinners among the believers who will stay in Hell for some time), when they the disbelievers see them being brought out of Hell."
Continue reading the tafsir of ayahs 1–3