Sahih Muslim 2558
Sahih Muslim · Book 45: The Book of Virtue, Enjoining Good Manners, and Joining of the Ties of Kinship · The Prohibition Of Mutual Jealousy And Hatred, And Turning Away From One Another
Anas b. Malik reported Allah's Messenger (ﷺ) as saying:
حَدَّثَنَا يَحْيَى بْنُ يَحْيَى ، قَالَ قَرَأْتُ عَلَى مَالِكٍ عَنِ ابْنِ شِهَابٍ ، عَنْ أَنَسِ بْنِ مَالِكٍ ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " لاَ تَبَاغَضُوا وَلاَ تَحَاسَدُوا وَلاَ تَدَابَرُوا وَكُونُوا عِبَادَ اللَّهِ إِخْوَانًا وَلاَ يَحِلُّ لِمُسْلِمٍ أَنْ يَهْجُرَ أَخَاهُ فَوْقَ ثَلاَثٍ " .
Neither nurse mutual hatred, nor jealousy, nor enmity, and become as fellow brothers and servants of Allah. It is not lawful for a Muslim that he should keep his relations estranged with his brother beyond three days.