“Whoever taunts a brother (Muslim) with a sin (which the Muslim had committed), will not die until he (the taunter) commits the same sin.”
This Hadeeth warns us of a very grave and serious consequence of looking down upon and mocking those who have repented of their sins. This is one reason (amongst others) why so many find themselves involved in major sins.
…When a person derides, scoffs and scorns at another person for his past sins, adopting an attitude of mock holiness, such a person is paving his way to the ditches of sins, and ends up falling into the very same sins.
These words of Rasulullah (Sallallaahu ‘alayhi waSallam) should not be taken lightly. …If a person mocks at or deliberately reminds another of his past sins – which the person had sincerely repented of, thus causing him or her grief and hurt, then as is mentioned in the Hadeeth, such a person should expect to find himself or herself in the same gutter of evil. (May Allah Ta’ala protect us all.)
How grave the situation would be if we mocked, jeered at, or disgraced a person who had sincerely repented of zina, or ribaa, or gambling, or drugs and alcohol ? Would we like the disgrace and stigma of that same sin in our lives ?
No, we would not. …We should therefore carefully reflect over this reality and curb any evil, foul tendency of the nafs to disgrace another person over sins already given up… If not, we will inevitably disgrace ourselves.
Rasulullah (Sallallaahu ‘alayhi waSallam) also said : “Whoever conceals the wrong-doings of a brother Muslim, Allah will conceal his wrong-doings on the Day of Judgment, and whoever will publicize the wrong-doings of a brother Muslim, Allah will disclose his wrong-doings to the people, so much so that he will be disgraced sitting in his own house.”
Allah Ta’ala has mentioned in the Qur’aan Shareef regarding those who make Taubah:
إِنَّ اللّٰهَ يُحِبُّ التَّوّٰبِينَ
“…Verily Allah loves those who repent…”
[Surah Baqarah 2 : 222]
When Allah Ta’ala, Himself, is stating that the one who has made sincere Taubah has become beloved to Him, who are we to criticize and condemn? His sin has been Divinely forgiven, and he has become a beloved of Allah Ta’ala.
Of course, if a person is indulging in sins – whether flagrantly or secretly, and one is aware, then in an approachable manner, with tact and wisdom, the duty of ‘Amr bil Maroof and Nahy anil Munkar’ should be carried out – encourage towards good, and forbid the evil.
We should keep in mind the Hadeeth :
‘ A sincere repenter of sins is like one
who has not committed sins.’
By Hazrat Maulana Yunus Patel (Rahmatullahi ‘alayh)
 Ribaa : usury
 Ibn Majah