Question: What should we do in case of learning about someone’s sin?
Answer: Conceal it. Disclosing it to another person without a valid Islamic reason is a sin and makes the disclosing-person worthy of the punishment of Hell. Make a habit of concealing the faults of Muslims because whoever conceals the fault of a Muslim has been given the glad tidings of Paradise. Sayyidunā Abū Sa’īd Khudrī رَضِىَ الـلّٰـهُ تَـعَـالٰی عَـنْـهُ reports, ‘Whoever sees a fault in his brother and then conceals it shall enter Paradise.’
(Musnad ‘Abd Ibn Ḥumayd, pp. 279, Ḥadīš 885)
So if we ever learn that مَـعَـاذَ الـلّٰـه عَزَّوَجَلَّ someone has committed adultery or homosexuality, misused his eyes, told a lie, broken a promise or backbitten, or committed any other crime secretly and there is no Islamic benefit in exposing it, then it is necessary for us to conceal it and it shall be a sin for us to expose it to others. Certainly, no one will be able to bear the punishment for backbiting and disgracing people.
Question: Please tell us the punishment for backbiting and disgracing people!
Answer: On the night of Mi’rāj one of the spectacles that our Beloved and Blessed Prophet صَلَّى اللهُ تَعَالٰى عَلَيْهِ وَاٰلِهٖ وَسَلَّم witnessed was a group of people scratching their faces and chests with their nails which were made of copper. When he صَلَّى اللهُ تَعَالٰى عَلَيْهِ وَاٰلِهٖ وَسَلَّم enquired about them, he صَلَّى اللهُ تَعَالٰى عَلَيْهِ وَاٰلِهٖ وَسَلَّم was told, ‘They used to eat the flesh of people (i.e. they used to backbite) and dishonour them.’
(Sunan Abī Dāwūd, vol. 4, pp. 353, Ḥadīš 4878)
For further details, please buy and read book ‘Backbiting – A Cancer in our Society’ published by Maktaba-tul-Madīnaĥ.