It is narrated from Sayyiduna Abu Ayyub (may Allah be pleased with him) that the Prophet of Allah (peace and blessings be upon him) said: "Do not cut off relations, do not turn your backs on one another, and be, O servants of Allah, brothers. The believers' cutting off of one another is for up to three days; then if they do not speak, Allah turns away from them both until they speak."
Hadith Referenceالمعجم الكبير للطبراني / باب الخاء / 3959