Combing the Hair - Section 2 Mishkat al-Masabih 4438

Arabic hadith text
وَعَنْ زَيْدِ بْنِ أَرْقَمَ أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ: «مَنْ لَمْ يَأْخُذ شَارِبِهِ فَلَيْسَ مِنَّا» . رَوَاهُ أَحْمَدُ وَالتِّرْمِذِيُّ وَالنَّسَائِيُّ
Translation

Zaid b. Arqam reported God’s messenger as saying, “He who does not take something off his moustache is not one of us.” Ahmad, Tirmidhi and Nasa'i transmitted it.