Cover your brother’s disgrace as much as possible. Because it could be that he just slipped and will soon repent. Everyone makes mistakes.
In a hadith from Abu Hurairah (may Allah blesses him), that the Prophet (ﷺ) says,
وَمَنْ سَتَرَ مُسْلِمًا سَتَرَهُ اللَّهُ فِي الدُّنْيَا وَالآخِرَةِ
“Allah will cover up on the Day of Resurrection the defects (disgrace) of the one who covers up the disgrace of the others in this world and in the Hereafter” [Saheeh Muslim].
But don’t get me wrong, it doesn’t mean you can support mistakes and injustices. If your brother takes someone else’s rights, then advise him to take responsibility for it. Because if not, he will be responsible for it in the afterlife. Because the Prophet (ﷺ) also says:
من كانت له مظلمة لأخيه من عرضه أو شيء فليتحلله منه اليوم قبل أن لا يكون دينار ولا درهم إن كان له عمل صالح أخذ منه بقدر مظلمته وإن لم تكن له حسنات أخذ من سيئات صاحبه فحمل عليه
“He who has done a wrong affecting his brother’s honour or anything else, let him ask his forgiveness today before the time (i.e., the Day of Resurrection) when he will have neither a dinar nor a dirham. If he has done some good deeds, a portion equal to his wrong doings will be subtracted from them; but if he has no good deeds, he will be burdened with the evil deeds of the one he had wronged in the same proportion” [Al-Bukhari].
So, cover up your brother’s mistakes when they deserve to be covered. But in the other hand, advise him to take responsibility for his mistakes if he takes someone else’s rights.
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