JAMI AL-TIRMIDHI

Intertwine the beard
  (29)

Sayyidina Hassan Ibn Bilal (RA) said that he saw ammar ibn yasir (RA) perform ablution,
He  ran  his  fingers  through  beard  so  Hassan  (RA)  asked  him,  "Do  you  interwine your
beard?"  Ammar  (RA)  said  ,  "Why  should  I  not  do  it  when  I  did  see  Allah’s  Messenger
(SAW) run fingers through his beard"
 
[Ibn e Majah 429,430]