Reference: Siyar A’laam an-Nubalaa v11 p33
When would sit before the barber to have his moustache trimmed, he would engage in the glorification of Allaah. So the barber would say to him:
‘Can you just shutup for a while!’ And he would respond:
‘You just do your job [and leave me to my remembrance of Allaah].’
