Mu'adh ibn Jabal said, "When you have love for your brother, do not quarrel with him or treat him badly nor ask questions about him, It may be that an enemy of his will appear and say something about him which is not true and will thereby cause a split between you."  

أَنَّهُ قَالَ إِذَا أَحْبَبْتَ أَخًا فَلاَ تُمَارِهِ وَلاَ تُشَارِّهِ وَلاَ تَسْأَلْ عَنْهُ فَعَسَى أَنْ تُوَافِيَ لَهُ عَدُوًّا فَيُخْبِرَكَ بِمَا لَيْسَ فِيهِ فَيُفَرِّقَ بَيْنَكَ وَبَيْنَهُ  

'Abdullah ibn 'Amr reported that the Prophet, may Allah bless him and grant him peace, said, "Anyone who has love for his brother in Allah and for Allah should say, 'I love you for Allah,' and they will both enter the Garden. The one who has love for someone in Allah has a degree over the one he loves because of his love."  

عَنِ النَّبِيِّ ﷺ قَالَ مَنْ أَحَبَّ أَخًا لِلَّهِ فِي اللهِ قَالَ إِنِّي أُحِبُّكَ لِلَّهِ فَدَخَلاَ جَمِيعًا الْجَنَّةَ كَانَ الَّذِي أَحَبَّ فِي اللهِ أَرْفَعَ دَرَجَةً لِحُبِّهِ عَلَى الَّذِي أَحَبَّهُ لَهُ