Ayah 17 of Surat Al-A^la means: The Hereafter is more beneficial and everlasting.
There is no doubt and no question about the rewards in the Hereafter being magnificent and everlasting. This means that the pleasures of Paradise are superior in quality and quantity and longer lasting than the pleasures of this world. Also with no doubt, the one who is clever and intelligent will discipline one’s self and work towards gaining the pleasures of life after death, applying the traditions of goodness urged by the Prophet of Allah, peace be upon him.
The person is usually given one life in this world, so a person is wise to live this life correctly.
Those among mankind and jinn who believe correctly in Allah, and believe in the Messenger sent to them and profess their belief (i.e., becoming followers of the true Religion) and die with that status will dwell forever in Paradise. The life in Paradise is better than what any human living on earth can imagine.
Those in Paradise will experience enjoyment by body and soul, but the body will be a new body with no defects. Paradise is not fictional. It is very real and actual. There will be wonderful riches, foods, joy, and peace. Those in Paradise will be in ranks according to their piety. Those who are rewarded with Paradise will never be sent out of it.
Hell, however, is the everlasting dwelling place for those humans and jinn who rejected the revelations of the prophets. Hence, they disbelieved in Allah and His messengers. Hell is also a particular place and is not experienced here on earth. Its torture will not cease. The suffering will also be by the body and the soul. Some humans who were followers of the true Religion will suffer in Hell for some time, because they had sinned and had not repented of their sins during their lifetime.
But, because they were believers of the true Religion, they will get out of Hell after spending the time which Allah willed for them. Then they will enter Paradise and dwell there forever and receive no further punishment. Some believers of the true Religion who die as sinners will be forgiven by Allah on the Day of Judgment, out of His generosity, and will not go to Hell, although they deserve to, before entering Paradise; they will go to Paradise directly.
The Prophet said what means the following: Hellfire was lit for a thousand years until it turned red and then for another thousand years until it turned white, and for a further one thousand years until it turned black and now it is absolutely pitch-black.
As for its intensity, it has been mentioned in a hadith that the most extreme fire in this life is but one of seventy when compared to the extremity of the blazing Hellfire. Thus, it is of extreme temperature and great depth that we cannot conceive.
It is mentioned that once the Prophet was amongst his companions when they heard a loud sound. The Prophet asked the companions if they knew what this noise was. They replied: “Allah and his messenger know best.” He replied what means: “It is a rock that had been thrown into Hell seventy years earlier and just now it reached the bottom.”
When we stop and think how intolerable the fire of this life is? Even the sun’s heat at many times is unbearable, then we should realize that we cannot bare the severity of Hellfire in the Hereafter. This is the fire that is fueled by people and stones.
We ask Allah to save us from Hellfire and make us amongst those who will be admitted into Paradise without prior torture. Ameen.