مُسْنَدُ أَحْمَدَ
Musnad Ahmad 3664
Musnad of Abdullah bin Mas'ood
It was narrated that ‘Abdullah (رضي الله عنه) said: The Messenger of Allah (ﷺ) said: “(Believing in) bird omens is shirk." There is no one among us who does not (think of them), but Allah takes away (such thoughts) by means of putting trust in Him.
Musnad Ahmad 3687Its isnad is saheeh]