This incident happened to me a decade and a half ago. Me and a friend were riding in a taxi and the cab driver had a big beard. We were both oblivious at the time to why a Muslim male had to grow his beard (it is not necessary for females to do so) so long.

The man, who was very well spoken, answered that we were in error(and this is were you have to speak arabic or at least be familiar with the language to understand his answer.) He said that he didn’t grow his beard but it raised him… In arabic to grow is the same word as to raise or to discipline, So in fact he said that his beard disciplines him because whenever he considers performing a sin or any form of deviation. Seeing his beard or stroking his beard (which is something that most big  bearded folk do unconsciously) reminds him that he, as a representative of the faith and as a devout muslim… cannot commit these transgressions.

Years later I was asked the same question that I myself asked the Cab driver… and I gave the same answer, because that is exactly how it is.