Sahih Muslim
The Book of Virtue, Good Manners and Joining of the Ties of Relationship (Kitab Al-Birr was-Salat-I-wal-Adab)
Book Number: 032 / Hadith Number: 6210
Anas reported Allah's Apostle (may peace be upon him) as saying: Nurse no grudge, nurse no aversion and do not sever ties of kinship and live like fellow-brothers as servants of Allah. This hadith has been narrated on the authority of Shu'ba with the same chain of transmitters but with this addition:" As Allah has commanded you."