The Prophet ﷺ said, "Every traitor will have a banner on the Day of Resurrection by which he will be recognized."
عن النبي ﷺ قال: لكل غادر لواء يوم القيامة يعرف به.
Bukhari narrated it in "Jizya and Truce" (3187), and Muslim narrated it in "Jihad and Expeditions" (1737:14), via Shubah, from Thabit, from Anas, who related it.