Muwatta Malik #1774

Yahya related to me from Malik from Suhayl ibn Abi Salih from his father from Abu Hurayra that the Messenger of Allah, may Allah bless him and grant him peace, said, "The doors of the Garden are opened on Monday and Thursday. Every muslim slave who does not associate anything with Allah is forgiven except for the man who has enmity between him and his brother. It is said, 'Leave these two until they have made a reconciliation. Leave these two until they have made a reconciliation.' "