مُسْنَدُ أَحْمَدَ
Musnad Ahmad 2474
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
'Abdullah bin Sa'eed bin Abi Hind narrated, from one of the companions of ‘Ikrimah, who said: The Messenger of Allah (ﷺ) used to notice things whilst praying, without turning his neck.
Musnad Ahmad 2486This is mursal]