Re: speaking of a beard...
"This day have I perfected for you your religion and completed My favor on you and chosen for you Islam as a religion." -- Qur'an 5:3
The cultural practices (the beard is a good example) that many consider a necessary part of the religion actually become part of Islam after this day that Allah perfected the religion*.*
Semi, there is absolutely no connection between this verse and the Sunnah of beard. Chronologically this verse revealed when the Prophet SAW was not to remain among the people for long.
What people in my opinion (including the majority of muslims) do not understand is that anything the Prophet SAW did is regarded as Sunnah. To me a sunnah which is explaining something from the Quran has religious significance whereas others do not but are simply accounts of Arabic cultural practices which were not against Islam. Some were politically motivated and some were economically centric, they have some principles behind them but there application is not etched in stone. It is true at least in my opinion that muslims have taken the status of sunnah to the extreme.