Riyad as-SalihinChapter 17Hadith 979
Full Sharh — Riyad as-Salihin 979
وعن ابن مسعود رضي الله عنه قال: قال رسول الله صلى الله عليه وسلم : "ليس منا من ضرب الخدود، وشق الجيوب، ودعا بدعوى الجاهليه" ((متفق عليه)).
English Translation
Ibn Mas'ud (May Allah be pleased with him) said:: The Messenger of Allah (ﷺ) said, "He who (on befalling a calamity) slaps his cheeks, tears his clothes and follows the ways and traditions of the Days of Ignorance is none of us.".
Source
Riyad as-Salihin(رياض الصالحين)
The Book of the Prohibited actions
Hadith Number
979