(68) رَبَّنَآ ءَاتِهِمْ ضِعْفَيِنِ مِنَ الْعَذَابِ وَالْعَنْهُمْ لَعْناً كَبِيراً
68. "O' our Lord! Give them double chastisement and curse them with a great curse."
This holy verse indicates that on the Day of Hereafter the misguided hellish people will be excited and ask for a grievous punishment from Allah (s.w.t.) for those who misguided them. They will ask Him to give them two kinds of punishment, one punishment for their own aberration and another one for their misleading them. They say:
them with a great curse."
It is certain that they deserve a curse and chastisement, but 'double chastisement' and ' a great curse' is for the attempt that they applied for leading others astray.
It is interesting that in Sura Al-'A'rāf, No. 7, when these aberrant followers ask a double chastisement for their leaders, they will be told: "…For each one there is double (chastisement), but you do not know'." That is, there will certainly be a double chastisement both for them and for you.
The double chastisement for the leaders of disbelief and aberration is clear, but the double chastisement for the aberrant followers is a question.
The reason of it is that they have a punishment for their aberration, and another one for the sake of their strengthening
 Sura Al-'A'rāf, No. 7, verse 38
and helping the unjust ones, because the unjust ones can not do anything by themselves, but their friends and helpers assist them in increasing their injustice and their infidelity, though in comparison, the punishment of the leaders is more grievous and more painful.
* * * *