Sunan Ibn Majah 3632

Abū Bakr ibn Abī Shaybah narrated to us; Yaḥyā ibn Ādam narrated to us, from Ibrāhīm ibn Saʿd, from al-Zuhrī, from ʿUbayd Allāh ibn ʿAbd Allāh, from Ibn ʿAbbās, who said: The People of the Book used to let their hair hang down, while the polytheists used to part their hair. The Messenger of Allah, may Allah bless him and grant him peace, liked to conform to the People of the Book. So the Messenger of Allah let his forelock hang down, then later parted his hair.