Riyad as-Salihin
Riyad as-Salihin 1585
Prohibition of the Treachery and Breaking one's Covenant
Arabic hadith text
وعن ابن مسعود، وابن عمر، وأنس رضي الله عنهم قالوا: قال النبي صلى الله عليه وسلم : " لكل غادر لواء يوم القيامة، يقال: هذه غدرة فلان" ((متفق عليه)).
Translation
Ibn Mas'ud, Ibn 'Umar and Anas (May Allah be pleased with them) said
The Prophet (ﷺ) said, "For every one who breaks his covenant, there will be a (huge) flag on the Day of Resurrection and it will be said: 'This flag proclaims a breach of covenant by so-and-so."'[Al-Bukhari and Muslim].