"...So, fight your desires at a time when you can eat. The soul is never satisfied. Satisfying your desires is like satisfying the thirsty person who went to drink water from the sea - the more he drinks, the thirstier he gets, since the water is salty.
These Romans used to eat all types of food and sweets to the point that they no longer felt the pleasure in eating food. So, they would fast in order to once again feel the taste of their food. Likewise, they drowned in sex to the point that they hated women. So, they would move far away from the cities until they once again longed for women.
The Europeans opened the door of sexuality as far as it could be opened, and sex became as widespread as food, drink, and oxygen. As a result, they now see endless cases of rape, sexually transmitted disease, etc. This is because desires are never satisfied. Whenever you nourish them, they increase in hunger:
And the soul increases in desire when you awaken its desire * And if it is restricted to little, it becomes content.
Jabir was once walking to the marketplace. So, 'Umar asked him: "Where are you going, Jabir?" He said: "My soul longed for some meat, and I want to go buy some meat with a dirham." 'Umar replied: "O Jabir! Whenever you have the desire for something, you go out and buy it?"
One time, 'Umar had some food placed in front of him, and he began to weep. It was asked of him: "Why are you weeping, O Commander of the Believers?" He said: "I am afraid that it would be said to me on the Day of Judgement:
وَيَوۡمَ يُعۡرَضُ ٱلَّذِينَ كَفَرُواْ عَلَى ٱلنَّارِ أَذۡهَبۡتُمۡ طَيِّبَـٰتِكُمۡ فِى حَيَاتِكُمُ ٱلدُّنۡيَا وَٱسۡتَمۡتَعۡتُم بِہَا فَٱلۡيَوۡمَ تُجۡزَوۡنَ عَذَابَ ٱلۡهُونِ بِمَا كُنتُمۡ تَسۡتَكۡبِرُونَ فِى ٱلۡأَرۡضِ بِغَيۡرِ ٱلۡحَقِّ وَبِمَا كُنتُمۡ تَفۡسُقُونَ
"On the Day when those who disbelieve will be exposed to the Fire, it will be said: 'You received your good things in the life of the world, and you took your pleasure therein. Now, this Day, you shall be recompensed with a torment of humiliation because you were arrogant in the land without a right, and because you used to rebel and disobey.'"
Therefore, it should be everyone's goal to be abstinent from worldly pleasures and to fight their desires, since it is impossible for the soul to rise and ascend except if it dominates over its desires and whims. The soul that becomes a prisoner to its desires will never be able to face the enemy on the battlefield. So, if you wish to remain travelling upon the path to Allah, hold yourself back.
Unfortunately, this type of knowledge is not taught in the universities or schools - the knowledge of behavior and conduct (suluk). This knowledge is missing because there are no murabbin, and it is not taught in al-Azhar or other colleges of Shari'ah - the science of behavior and manners, the science of nurturing the soul, the science of tarbiyah.
So, you sometimes find the youth who has memorized much - ma Sha' Allah - from many books and ahadith: he read 'Riyad as-Salihin' from a while back, he studied 'Rawdat an-Nadhir,' he read 'Nayl al-Awtar,' 'Subul as-Salam,' 'Fath al-Bari,' etc. Despite this, you never find him fasting any optional fasts or praying at night. His soul is dead. He prays no optional prayers, and he follows every license of ease (rukhsah) that he comes across. Why? Because his soul is sick. He did not nurture himself. And his desires...I seek refuge with Allah!"
['at-Tarbiyah al-Jihadiyyah wal-Bina''; 1/367-368]
(SHEIKH 'ABDULLAH YUSUF 'AZZAM (ASY-SYAHID, INSYAALLAH)