From Sahih Muslim (Hadith 6547):
Abu Huraim reported Allah's Messenger (ﷺ) as saying The deeds of people would be presented every week on two days, viz. Monday and Thursday, and every believing servant would be granted pardon except the one in whose (heart) there is rancour against his brother and it would he said:Leave them and put them off until they are turned to reconciliation
Reference: Muslim 6547