كتاب البر والصلة والآداب
45
The Book of Virtue, Enjoining Good Manners, and Joining of the Ties of Kinship
(11)
Chapter: The Prohibition Of Holding Grudges
(11)
باب النَّهْىِ عَنِ الشَّحْنَاءِ، وَالتَّهَاجُرِ، ‏‏

Abu Huraira reported it as a marfu' hadith (and the words are):

The deeds are presented on every Thursday and Monday and Allah, the Exalted and Glorious. grants pardon to every person who does not associate anything with Allah except the person in whose (heart) there is rancour against his brother. It would be said: Put both of them off until they are reconciled.
حَدَّثَنَا ابْنُ أَبِي عُمَرَ، حَدَّثَنَا سُفْيَانُ، عَنْ مُسْلِمِ بْنِ أَبِي مَرْيَمَ، عَنْ أَبِي صَالِحٍ، سَمِعَ أَبَا هُرَيْرَةَ، رَفَعَهُ مَرَّةً قَالَ ‏ "‏ تُعْرَضُ الأَعْمَالُ فِي كُلِّ يَوْمِ خَمِيسٍ وَاثْنَيْنِ فَيَغْفِرُ اللَّهُ عَزَّ وَجَلَّ فِي ذَلِكَ الْيَوْمِ لِكُلِّ امْرِئٍ لاَ يُشْرِكُ بِاللَّهِ شَيْئًا إِلاَّ امْرَأً كَانَتْ بَيْنَهُ وَبَيْنَ أَخِيهِ شَحْنَاءُ فَيُقَالُ ارْكُوا هَذَيْنِ حَتَّى يَصْطَلِحَا ارْكُوا هَذَيْنِ حَتَّى يَصْطَلِحَا ‏"‏ ‏.‏
Reference : Sahih Muslim 2565 c
In-book reference : Book 45, Hadith 44
USC-MSA web (English) reference : Book 32, Hadith 6223
  (deprecated numbering scheme)