As is described in A Guide For Youth, there is no doubt that youth will depart; it will change into old age and death as certainly as the summer gives its piace to autumn and winter, and the day changes into evening and night. All the revealed scriptures give the good news that if fleeting, transient youth is spent on good works, in chastity and within the bounds of good conduct, it will gain for the person immortal youth.
If, on the other hand, youth is spent on vice, just as murder resulting from a minute's anger leads to millions of minutes of imprisonment, so quite apart from being called to account in the hereafter, and the torments of the grave, and the regrets arising from their passing, and sins, and the penalties suffered in this world, the unlawful pleasures of youth contain more pain than pleasure; every youth with sense will corroborate this from his own experience.
For example, the pains of jealousy, separation, and unreciprocated love transform the partial pleasure to be found in illicit love into poisonous honey. If you want to know how they end up in hospitals due to illnesses resulting from their misspent youth, and in prison due to their excesses, and in bars and dens of vice and the graveyard due to the distress arising from their unnourished hearts and spirits not performing their right functions, go and ask at the hospitals, prisons, bars, and graveyards. More than anything, you will hear the weeping and sighs of regret at the blows youths have received as the penalty for abusing their youth, and their excesses, and illicit pleasures.
Foremost the Qur'an, with numerous of its verses, and all the revealed scriptures and books, give the glad tidings that if spent within the bounds of moderation, youth is an agreeable Divine bounty and sweet, powerful means to good works, which yields the result of shining, immortal youth in the hereafter.
Since lhe reality is this, and since the bounds of the licit are sufficient for enjoyment, and since an hour of unlawful pleasure leads sometimes to a punishment of one, or ten, years' imprisonment; surely it is absolutely nec¬essary to spend the sweet bounty of youth chastely, on the straight path, as thanks for the bounty.