Praise be to Allah.
It was reported in Saheeh Muslim that Abu Sa’eed al-Khudri (may Allaah be pleased with him) said: “The Messenger of Allaah (peace and blessings of Allaah be upon him) said: ‘As for the people of Hell, they are its inhabitants, and they neither live therein nor die. But there are people who will enter Hell because of their sins – or mistakes – so Allaah will cause them to die once, then when they become like coal, He will give permission for intercession (for them). They will be brought group by group to the rivers of Paradise. Then it will be said: “O people of Paradise! Pour water on them.” Then they will grow like seeds (i.e., the seeds of herbs and aromatic plants, or it was said, small plants that grow in between grasses, or it may mean wheat).’”
The scholars said: “What is meant by the people of Hell are its kaafir inhabitants, who will never come out of it and never die at all.
Allaah says (interpretation of the meaning):
“But those who disbelieve (in the Oneness of Allaah), for them will be the Fire of Hell. Neither will it have a complete killing effect on them so that they die, nor shall its torment be lightened for them. Thus do We requite every disbeliever!” [Faatir 35:36]
As for the sinners among those who believe in the Oneness of Allaah, those who have committed major sins (kabaa’ir), they will be punished in accordance with the degree of their sins for a period decreed by Allaah, then they will die a lesser death such that they no longer feel anything, for a period decreed by Allaah. Then they will be brought out dead, turned into coals and carried like luggage, and they will be thrown into the rivers of Paradise and the water of life will be poured over them. Then they will grow, like wheat at first, but quickly, like herbs. Then they will get stronger and be fully formed, and will be taken to their homes in Paradise. And Allaah knows best.