I am asking you what to do if one has a friend who practices unlawful sexual intercourse. This friend persists on this act although I forbade him to do it. Is it permissible to threaten him with informing his father that he practices fornication or with something greater than that?
All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
You should do your utmost in advising that young man while scaring him from Allaah Almighty and explaining the evil of the act that he is practicing. It is one of the major, heinous and grave sins, for it combines violation of the commands of Allaah Almighty, transgressing against the honor of people, and indulging in the swamps of dissoluteness and vices that no sane person approves for himself.
Allaah Almighty says (what means):
• {And do not approach unlawful sexual intercourse. Indeed, it is ever an immorality and is evil as a way.} [Quran 17: 32]
• {And those who do not invoke with Allaah another deity or kill the soul which Allaah has forbidden [to be killed], except by right, and do not commit unlawful sexual intercourse. And whoever should do that will meet a penalty. Multiplied for him is the punishment on the Day of Resurrection, and he will abide therein humiliated. Except for those who repent, believe and do righteous work. For them Allaah will replace their evil deeds with good. And ever is Allaah Forgiving and Merciful.} [Quran 25: 68-71]
It has been authentically reported that ‘Abdullaah ibn Mas‘ood said: “O Messenger of Allaah, which sin is the worst?” He, sallallaahu ‘alayhi wa sallam, said, “Setting up a rival to Allaah although He is the One Who created you.” [‘Abdullaah] said: “Then what?” He, sallallaahu ‘alayhi wa sallam, said, “Killing your child for fear that he may share your food.” [‘Abdullaah] said, “Then what?” He, sallallaahu ‘alayhi wa sallam, said, “Committing unlawful sexual intercourse with your neighbor's wife.” [Al-Bukhari and Muslim]
The Prophet, sallallaahu ‘alayhi wa sallam, also said: “Nobody who commits unlawful sexual intercourse is a believer at the moment when he is doing so.” [Al-Bukhari and Muslim]
There are many other verses and Ahaadeeth that warn against committing that heinous act. If you explain that to him, he might listen to your advice and repent to Allaah Almighty. Also, your advice could bring him back to his senses and cause him to adopt the way of the righteous.
If he insists on committing immorality and does not listen to your advice, then threaten him that you will expose his matter and spread it among people, including his father.
Let that be just a threat for him and do never tell anyone about what he is doing because this is a form of spreading immorality and, also, because concealing his fault is required, especially if telling others about his sin will avail nothing in carrying out the prescribed corporal punishment nor serve as an effective deterrent.
Once you have determined that advice is useless for him, you should forsake and abandon him and not sit with him after that.
Allaah Knows best.
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