The Cow - 2:217
"They ask you about fighting in the Holy Month. Say: "Fighting on it is a great sin. But to turn away from the way of Allah and to be ungrateful to Him and to the Holy Mosque and to drive out its people from it is a greater sin with Allah. For oppression and cruelty is a greater crime than killing."If they could, they would fight you until they turn you back from your religion. Whoever of you turns away from his religion and dies as an unbeliever, all that he did will be in vain in this world and in the Hereafter. They are the people of the Fire and will abide therein forever."
The eternity of Paradise and Hell:
Prophet Abraham/14:48
On the Day when the earth is replaced by another earth and the heavens by other heavens, and everyone is brought before Allah, the One and the Most High.
Prophet Hud/11:106
The unfortunate are in the Fire. They will groan therein.
Prophet Hud/11:107
They will abide therein as long as the heavens and the earth endure, except if your Lord wills. Your Lord is the Doer of whatever He wills
Prophet Hud/11:108
And those who deserve happiness will abide in Paradise as long as the heavens and the earth endure. Except if your Lord wills. This is an uninterrupted reward.