things he said one of them is the beard. In another prophetic tradition he stated that there are 10
things that are natural and only those people will for sake these natural things whose nature has been corrupted. And among them is keeping beard. Also, the prophet peace be upon him has emphasized in his instruction to keep beard and to cut mustaches. Any instruction is usually for obligation. Therefore, from the Koran and the prophetic traditions we know keeping beard is mandatory. Its length has been determined by scholars based on their review of the lifestyles of the companions of the prophet peace be upon him which is one fist length. In another prophetic tradition is stated that prophet’s beard used to come to his chest and he used to trim it from the sides.
One time a group of people came to the prophet peace be upon him they didn’t have complete beards so the prophet’s peace be upon him advised the companions to lengthen their beards and that to trim them is a big sin. This major sin has the element of continuity, sometimes sins are committed but they are once in awhile, but this sin is repeatedly committed. Some scholars have stated that this is a major sin along with that it is destruction of the symbol of Islam which doubles the sin in magnitude. Things that are symbolizing Islam must be protected. Other sins can be committed discreetly but this one cannot be committed like that.
One should not be bold with aggression specially if the person is violating the commands of Allah to be bold about it is very heinous. It is not acceptable and totally forbidden.