Hadith: He is not one of us who slaps the cheeks, splits the collars, and calls out with the calls of Jāhiliyyah (pre-Islamic era of ignorance)

عَنْ عَبْدِ اللَّهِ بنِ مَسْعُودٍ رَضِيَ اللَّهُ عَنْهُ قَالَ: قَالَ النَّبِيُّ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ:
«لَيْسَ مِنَّا مَنْ لَطَمَ الخُدُودَ، وَشَقَّ الجُيُوبَ، وَدَعَا بِدَعْوَى الجَاهِلِيَّةِ».
[صحيح] - [متفق عليه] - [صحيح البخاري: 1294]

‘Abdullah ibn Mas‘ūd (may Allah be pleased with him) reported: The Prophet (may Allah's peace and blessings be upon him) said:
"He is not one of us who slaps the cheeks, splits the collars, and calls out with the calls of Jāhiliyyah (pre-Islamic era of ignorance)."
[Authentic hadith] - [Narrated by Bukhari & Muslim] - [Sahih Bukhari - 1294]

Explanation

The Prophet (may Allah's peace and blessings be upon him) forbade and warned against some of the practices of the people of Jāhliyyah, saying: He is not one of us:
First: The one who slaps the cheeks, and the cheek is mentioned in particular because it is the part usually slapped; otherwise, slapping the rest of the face is included in the prohibition.
Second: The one who splits the opened part of the garment through which the head is entered due to severe discontentment.
Third: The one who calls out with the calls of the people of Jāhiliyyah, like supplicating for ruin and destruction, wailing, lamenting, etc.