Sahih Muslim | Book 32 | Hadith Number 6222

Narrated by Abu Huraira
Abu Huraira reported Allah's Messenger (may peace be upon him) as saying: The gates of Paradise are not opened but on two days, Monday and Thursday, and then every servant (of Allah) is granted pardon who does not associate anything with Allah except the person in whose (heart) there is rancour against his brother. And it would be said: Look towards both of them until there is reconciliation; look toward both of them until there is reconciliation; look towards both of them until there is reconciliation. This hadith has been narrated on the authority of Suhail who narrated it on the authority of his father with the chain of transmitters of MaIik, but with this variation of wording:,(Those would not be granted pardon) who boycott each other.