Is a man sinful if he shaves his moustache and leaves his beard? What is the Sunnah of the Messenger in this regard?
All Praise be to Allah Alone and peace and blessings be upon His Messenger, his family and Companions.
The Sunnah (supererogatory act of worship following the example of the Prophet) is to trim the moustache not to shave it as the Prophet (peace be upon him) stated:
Trim closely the moustache, and let the beard grow to be unlike the disbelievers.
Agreed upon Hadith.
However, there will be no sin upon him if he shaves it. Whereas it is obligatory to grow the beard for his statement (peace be upon him):
Trim closely the moustache, and let the beard grow to be unlike the disbelievers
.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.