It has been narrated on the authority of Abdullah that the Messenger of Allah (ﷺ) said:There will be for every perfidious person on the Day of Judgment a flag by which he will be recognised. It will be announced: Here is the breach of faith of so and so.
وَحَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا يَحْيَى بْنُ آدَمَ، عَنْ يَزِيدَ بْنِ عَبْدِ الْعَزِيزِ، عَنِ الأَعْمَشِ، عَنْ شَقِيقٍ، عَنْ عَبْدِ اللَّهِ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " لِكُلِّ غَادِرٍ لِوَاءٌ يَوْمَ الْقِيَامَةِ يُعْرَفُ بِهِ يُقَالُ هَذِهِ غَدْرَةُ فُلاَنٍ " .
Muslim
The Book ofJihadand Expeditions • Hadith 16