In whatever affair you may be, and whichever part of the Qur'an you recite, and whatever deed you do, We are witness over you when you are deeply engrossed therein. Not an atom's weight in the Earth and in the heaven escapes your Lord, nor is there anything smaller or greater, but it is in a Manifest Book. (10:61)
Certain angels are entrusted with recording everything that we do. God also has full knowledge and awareness of all our deeds, intentions, thoughts, and imaginings. Those who understand this (and act accordingly) will find true peace and happiness in both worlds. A family and community composed of such individuals would feel that they were living in Paradise.
Belief in the Resurrection prevents young people from wasting their lives in transitory and trivial things, and gives hope to the elderly as they move closer to the grave. It also helps children endure the death of loved ones. Children who believe that they will be reunited with their deceased loved ones in a far better world find true consolation in the Resurrection. Everyone, regardless of age, gender, and any other artificial human-devised difference, needs belief in the Resurrection as much as they need air, water, and bread.
As this belief leads people to a life of peace, intellectuals who seek public peace and security should emphasize it. Those who are convinced of what the Qur'an declares—Whoever does an atom's weight of good shall see it, and whoever does an atom's weight of evil shall see it (99:7–8)—live a responsible life, and a community composed of such people finds true peace and happiness. When this belief is inculcated in the hearts of young people, they will no longer be a harmful social element, but rather will seek to serve their nation and humanity.
Children are very sensitive and delicate. Extremely susceptible to misfortune, they also are easily affected by what happens to them and their families. When they lose a family member or become orphans, their world becomes dark and they fall into deep distress and despair. When one of my sisters died during my childhood, I was devastated. I frequently went to her grave and prayed from the bottom of my heart: "O God! Please bring her back to life again and let me see her beautiful face once more, or let me die so as to be reunited with her." So, what else other than belief in the Resurrection and reunion with deceased loved ones can compensate for the loss of parents, brothers and sisters, and friends? Children will find true consolation only when they are convinced that their beloved ones have flown to Paradise, and that they will be reunited with them.
How can you compesate the elderly for their past years, their childhood and youth that have been left behind? How can you console them for the loss of their loved ones who preceded them in death? How can you remove the fear of death and the grave from their hearts? How can you make them forget death, which they feel so deeply? Will more and newer worldly pleasures console them? Only convincing them that the grave, which seems to them like an open-mouthed dragon just waiting to devour them, is really a door to another and much better world, or simply a lovely waiting room opening onto that world, can compensate and console them for such losses.
In its inimitable style, the Qur'an voices such feelings through Prophet Zechariah:
This is a mention of your Lord's mercy unto His servant Zechariah; when he invoked Him with a secret, sincere call, saying: "My Lord, my very bones have become rotten and my head is shining with gray hair. My Lord! I have never been disappointed in my prayer to You." (19:2-5)
Fearing that his kinsmen would not be sufficiently loyal to his mission after his death, Prophet Zechariah, upon him be peace, appealed to his Master for a male heir to his mission. This is the cry of all old people. Belief in God and the Resurrection gives them the good news: "Do not be afraid of death, for death is not eternal extinction. It is only a change of worlds, a discharge from your life's distressing duties, a passport to an eternal world where all kinds of beauty and blessing wait for you. The Merciful One Who sent you to the world, and has kept you alive therein for so long a time, will not leave you in the grave's darkness and dark corridors opening onto the other world. He will take you to His Presence, give you an eternal and ever-happy life, and bless you with all the bounty of Paradise." Only such good news as this can console the elderly and enable them to welcome death with a smile.
Our free will, which we use to direct our life, makes us unique among all creatures. Free will is the manifestation of Divine Mercy and, if used properly, will cause us to be rewarded with the fruits of Mercy. Belief in the Resurrection is a most important and compelling factor urging us to use our free will properly and not to wrong or harm others.
Sahl ibn Sa'd narrates that God's Messenger was told of a young man who stayed at home for days. The Messenger, upon him be peace and blessings, went to visit him. When the young man saw the Messenger appear before him unexpectedly, he threw himself into the Messenger's arms and died instantly. The Messenger told those around him: "Lay out the corpse of your friend. Fear of Hell frightened him deeply. I swear by Him in Whose hand my life is that God will surely protect him from Hell."  The Qur'an declares: Those who fear to stand before their Lord and curb the desires of the carnal self, Paradise will be their dwelling place (79:40–41).
In a hadith qudsi, God says: "I will not unite two securities, nor two fears."  In other words, those who fear His punishment here will be protected from His punishment there, while those who do not fear His punishment here will not be saved from it there.
'Umar said, upon seeing a young man bravely protest and resist a wrong: "Any people deprived of the young are doomed to extinction." Young people have a transforming energy. If you let them waste it in triviality and indulgence, you undermine your own nation's future. Belief in the Resurrection stops young people from committing atrocities and wasting their energies on passing pleasures, and directs them to lead a disciplined, useful, and virtuous life.
 Kanz al-'Ummal, 3.141, Hadith No. 5878.
Belief in the Resurrection also consoles the sick. A believer who suffers from an incurable illness thinks: "I am dying; no one can prolong my life. Everyone must die. Fortunately, I am going to a place (Paradise) where I will recover my health and youth and enjoy them forever." Secure in this knowledge, all beloved servants of God, Prophets and saints, welcome death with a smile. The Last Prophet, upon him be peace and blessings, said during his final minutes of life: "O God, I desire the eternal company in the eternal world." He had informed his Companions the day before: "God let one of His servants choose between enjoying the beauty of this world as long as he wishes and what is with Him. The servant chose what is with Him."  The servant given this choice was the Messenger himself. The Companions understood whom he meant and burst into tears.
Similarly, when 'Umar ruled over a vast area stretching from the western frontiers of Egypt to the highlands of Central Asia, he prostrated himself before God and sighed: "I can no longer fulfil my responsibility. Let me die and be taken to Your Presence." Such a strong desire for the other world, the world of eternal beauty, and being blessed with the vision of the Eternally Beautiful One caused the Prophet, 'Umar, and many others to prefer death to this world.
The world is a mixture of good and evil, right and wrong, beauty and ugliness, and oppressors and oppressed. Many instances of wrong (appear to) go unnoticed, and numerous wronged people cannot recover their rights. Only belief in being resurrected in another world of absolute justice consoles the wronged and oppressed, and dissuades them from seeking vengence. Similarly, those stricken with affliction and misfortune find consolation in the Resurrection, because they believe that whatever befalls them purifies them, and that anything lost in a catastrophe will be restored in the Hereafter as a blessing of the Hereafter, just as if they had given these items as alms.
Belief in the Resurrection changes a house into a garden of Paradise. In a house where the young pursue their pleasures, children have nothing to do with religious sentiment and practices, parents are engrossed in procuring all fantasies of life, and grandparents live in a old-folks or nursing home and console themselves with pets, for there are no grandchildren around whom they can love and who can show them the respect they desire—in such a house, life is a burden difficult to bear. Belief in the Resurrection reminds people of their familial responsibilities, and as they implement these duties, an atmosphere of mutual love, affection, and respect begins to pervade the house.
This belief leads spouses to deepen their love and respect each other. Love based on physical beauty is temporary and of little value, for it usually disappears shortly after marriage. But if the spouses believe that their marriage will continue eternally in the other world, where they will be forever young and beautiful, their love for each other remains even though they gradually age and lose their physical beauty.
Such a belief-based family life makes its members feel that they are already living in Paradise. Similarly, if a country orders itself according to this same belief, its inhabitants would enjoy a life far better than what Plato imagined in his Republic or al-Farabi (Alpharabios) in his al-Madinat al-Fadila (The Virtuous City). It would be like Madina in the time of the Prophet, upon him be peace and blessings, or the Muslim lands under the rule of 'Umar, may God be pleased with him.
To have a better understanding of how the Prophet built that society, we provide several examples of his sayings concerning the Resurrection and the afterlife:
O people! You will be resurrected barefoot, naked, and uncircumcised. Listen to me with full attention: "The one who will be first clothed is Abraham, upon him be peace." Heed what I will say: "That day some from my Umma will be seized on the left side and brought to me. 'I will say: O Lord! These are my Companions.' I will be told: 'You do not know what disagreeable things they did after you.' Then I will say as the righteous servant [meaning Jesus] said: 'I was a witness over them while I continued to stay among them. When You took me You became the watcher over them. You are Witness over all things. If You punish them, they are Your slaves; if You forgive them, surely You are the All-Mighty, the All-Wise.'" 
Since God created them, the children of Adam have not experienced an event more terrible than death. However, death is easier than what will follow it. They will suffer such terror that sweat will cover their bodies until it becomes like a bridle around their chins, until it grows into something like a sea on which, if desired, vessels could be sailed. 
People will be resurrected in three groups: those who combined fear of God with expectation [fearing His punishment but never despairing of His mercy and forgiveness], those who [because they frequently "faltered"] will try to go to Paradise "mounted on a mule" in twos, threes, fours ... or tens. The rest will be resurrected into Fire; [since they constantly pursued sins worthy of Hellfire], if they want to sleep in the forenoon, Hell will go to sleep with them; when they reach night, Hell will reach night with them; when they reach morning, Hell will reach morning with them, and when they reach evening, Hell will reach evening with them. 
God's Messenger, upon him be peace and blessings, made sure that his Companions understood exactly what Hell was, and roused in them a great desire for Paradise by conveying its good tidings to them. As a result, they lived in great consciousness of Divine reward and punishment. They were so sensitive to religious obligations and the rights of people that, for example, two of them once appealed to the Messenger to solve a disagreement. After hearing them, the Messenger said:
I am a human being like you, so I will judge according to what you say. It is possible that one of you speaks more convincingly and I may judge in his favor. However, God will judge rightly in the Hereafter according to the truth of the matter. The wrongdoer will meet his due punishment, while the innocent will meet his reward. 
This was enough for each Companion to concede his claimed right. The Messenger advised them: "Divide the disputed goods in half, and then draw lots. Each one should consent to his share wholeheartedly and without regret."
Sa'd ibn Rabi' was severely wounded at the Battle of Uhud. While breathing his last, he whispered to Muhammad ibn Maslama, who brought him greetings from the Messenger: "Take my greetings to God's Messenger. By God, I sense the fragrance of Paradise behind Uhud."
 Bukhari, Anbiya', 8:48; Muslim, Jannah, 56; Tirmidhi, Qiyama,
 Ahmad ibn Hanbal, Musnad, 3:154. (Related by Anas.)
 Bukhari, Riqaq, 45; Muslim, Jannah, 59; Nasa'i, Jana'iz, 118. (Related by Abu Hurayra. Bukhari and Muslim.)
 Bukhari, Shahadah, 27; Muslim, 'Aqdiyah, 4; Abu Dawud, Adab, 87.