According to the Qur'an grief and unhappiness are attributes of unbelievers alone
What believers need to do at this time when great efforts are being made to spread and legitimize sadness is to usher in peace, together with joy.
Let them laugh little and weep much, in repayment for what they have earned. (Qur'an, 9:82)
They will say, “Our Lord, our wretchedness overcame us. We were misguided people.” (Qur'an, 23:106)
As we can see, unhappiness is equated with the unbelievers in the Qur’an. In the hereafter these people will blame their misguidance on “their wretchedness overcoming them.” Therefore, unhappiness is not something that God desires. Unhappiness is equated with the unbelievers in the Qur’an, and joy is equated with the believers.
In another verse, God reveals that there will be people who spurn the advice of the Qur’an because of their unhappiness:
He who has fear will be reminded; but the most miserable will shun it, (Qur'an, 87:10-11)
Almighty God has prohibited sorrow to all Muslims:
“Do not give up and do not grieve. You shall be uppermost if you are believers.” (Qur'an, 3:139)
Fanatics try to invalidate this commandment of God on the basis of false hadiths. They regard Muslims as suited to the unhappiness that God equates with the unbelievers. They seek to destroy joy, the greatest need of the soul and body. This is not something that God desires, however.
The joy in paradise and the true meaning of sorrow
God has created in paradise the way of life that He likes and loves; the life that our Lord praises and loves in paradise is therefore the ideal way of life for us. God reveals that people in paradise are in a state of joy:
As for those who had faith and did right actions, they will be made joyful in a verdant meadow. (Surat ar-Rum, 15)
Fanatics wish to deprive “joyful” Muslims of this joy of paradise by way of these false hadiths. They are not even aware of the true meaning of sorrow. To grieve in the face of an event is equivalent to saying “I wish it had not happened” and that, whether a person is aware of it or not, whether he does it knowingly or not, is rebellion against destiny. Yet fanatics should be aware that by making grief legitimate they are opposing God’s commandment and the destiny created by Him.
Faith is one of the greatest blessings that God can bestow on a person. For someone who has faith, the peace and happiness created in his heart by that faith are above all other things, even if he is deprived of the blessings of this world and is tested with the greatest of difficulties, and even if the circumstances all seem to be against him. God bestows peace and health on the heart that turns to Him, and happiness on the soul. It is impossible for someone who does not turn to God to be truly happy, even if he maintains otherwise. God may bestow the blessings of this world on such a person as part of the test and that person may seem to enjoy many blessings and delights. He may experience temporary desires and happiness. However, the longing in his soul will never allow him permanent happiness, or inner peace. In verse 28 of Surat ar-Ra’d, God says; “...those who have faith and whose hearts find peace in the remembrance of God. Only in the remembrance of God can the heart find peace.” Peace of mind depends on the bond to God alone.
Therefore, someone who truly believes in God is truly happy. Happiness is a secret that is compatible with human nature and that keeps a person healthy and sound. The cells remain healthy by means of happiness. The reason why happiness has such a positive effect is that, all things which are compatible with human nature are good things recommended by God. God has created laughter, joy and happiness as good things. Sorrow, on the other hand, has severely damaging effects that lead to physical and psychological harm.