مُسْنَدُ أَحْمَدَ
Musnad Ahmad 3647
Musnad of Abdullah bin Mas'ood
It was narrated that ‘Abdullah (رضي الله عنه) said: The Messenger of Allah (ﷺ) said, then the colour of his face changed, then he said something like that or something similar to that.
Musnad Ahmad 3670A saheeh report]