"1 saw Ammar bin Yasir performing Wudu, so he went through his beard (with his hand). It was said to him" - or he said - "1 said: 'You go through your beard?' He said: 'And what is there to prevent me? Indeed I saw Messenger of Allah going through his beard.'"  

وَمَا يَمْنَعُنِي وَلَقَدْ رَأَيْتُ رَسُولَ اللَّهِ ﷺ يُخَلِّلُ لِحْيَتَهُ  

the same from the Prophet.  

عَنِ النَّبِيِّ ﷺ مِثْلَهُ  

the Prophet would go through his beard."  

أَنَّ النَّبِيَّ ﷺ كَانَ يُخَلِّلُ لِحْيَتَهُ