Muwatta Malik, Book 47, Hadith 3 (USC-MSA) ⓘ
Yahya related to me from Malik from Ibn Shihab from Ali ibn Husayn ibn Ali ibn Abi Talib that the Messenger of Allah, may Allah bless him and grant him peace, said, "Part of the excellence of a man's Islam is that he leaves what does not concern him."
وَحَدَّثَنِي عَنْ مَالِكٍ، عَنِ ابْنِ شِهَابٍ، عَنْ عَلِيِّ بْنِ حُسَيْنِ بْنِ عَلِيِّ بْنِ أَبِي طَالِبٍ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " مِنْ حُسْنِ إِسْلاَمِ الْمَرْءِ تَرْكُهُ مَا لاَ يَعْنِيهِ " .
also referenced under: Book 47, Hadith 1638 (In-Book)