(191) بَابُ الْمُهْتَجِرَيْنِ
Hisham ibn 'Amir heard the Messenger of Allah, may Allah blesshim and grant him peace, say, "It is not lawful for a Muslim to snub anotherMuslim for more than three nights. As long as they are cut off from eachother, they are turning away from the Truth. The first of them to returnto a proper state has his expiation for that inasmuch as he was the firstto return to a proper state. If they die while they are cut off from oneanother, neither of them will ever enter the Garden."
Reference: Al-Adab Al-Mufrad 407
In-book reference: Book 22, Hadith 11
English translation: Book 22, Hadith 407