"The Messenger of Allah ﷺ said: 'Whoever does not trim his mustache, he is not from one of us.'" (Using translation from Nasāʾī 13)   

عَنِ النَّبِيِّ ﷺ قَالَ «مَنْ لَمْ يَأْخُذْ مِنْ شَارِبِهِ فَلَيْسَ مِنَّا»