مُسْنَدُ أَحْمَدَ
Musnad Ahmad 3877
Musnad of Abdullah bin Mas'ood
It was narrated from ‘Abdullah (رضي الله عنه) that The Prophet (ﷺ) said: "For every betrayer there will be a banner on the Day of Resurrection.”
Musnad Ahmad 3900Its isnad is saheeh, al-Bukhari (3184) and Muslim (1736)]