حَدَّثَنَا عَبْدُ اللهِ بْنُ صَالِحٍ قَالَ: حَدَّثَنِي مُعَاوِيَةُ، أَنَّ أَبَا الزَّاهِرِيَّةِ حَدَّثَهُ، عَنْ جُبَيْرِ بْنِ نُفَيْرٍ، عَنْ مُعَاذِ بْنِ جَبَلٍ أَنَّهُ قَالَ: إِذَا أَحْبَبْتَ أَخًا فَلاَ تُمَارِهِ، وَلاَ تُشَارِّهِ، وَلاَ تَسْأَلْ عَنْهُ، فَعَسَى أَنْ تُوَافِيَ لَهُ عَدُوًّا فَيُخْبِرَكَ بِمَا لَيْسَ فِيهِ، فَيُفَرِّقَ بَيْنَكَ وَبَيْنَهُ.
It is narrated from Sayyiduna Mu'adh bin Jabal (may Allah be pleased with him), he said: When you love your brother, never quarrel with him, nor treat him badly, nor ask anyone about him. It may happen that you meet one of his enemies, and he tells you something about him which is not true, and thus he creates separation between you.