All the ‘ulama’ of as-Salaf us-Salih, including the Four Imams, agree that shaving the beard is haram. They consider shaving it an impermissible mutilation, as has been reported from Umar Bin Abdul Aziz- [At-Tarikh by Ibn Asakir]. They considered the man who shaved his beard effeminate. Many of them would not accept his testimony or allow him to lead the prayers. Furthermore the 4 madhahib do not disagree on this issue either.
Ahnaf:
“It is prohibited for a man to cut his beard ... as for cutting it shorter than a fist-length - as is done by some people from the west and by the effeminate men - no one permits this. And as for shaving it completely, it is the doing of the Indian Jews and the PersianMagians” [Persian Magians-Followers of an old religion, possibly the same as the "Zoroastrians"] [Ad-Durr ul-Mukhtar].
Ibn-Abidayn said:
“It is prohibited for a man to cut his beard.” (Radd ul-Muhtar [2:418])
Malikiyyah:
“Shaving the beard is prohibited, as is cutting it if it causes a (clear) mutilation. But if it becomes oversized, and if cutting it would not appear as a mutilation, then it may be cut; but that would be disliked and contrary to that which is better.” [Sharh-ur-Risalah by Abu al-Hasan, and the commentary on it by al-Adwi]
Al-`Adwi said:
“It has been reported from Malik that he hated shaving anything under the jaws, until he said, ‘It is from the doing of the Magians.’ And it is prohibited to remove the hair of the beard.” [Sharh-ur-Risalah by Abu al-Hasan, and the commentary on it by al-Adwi (2:411)]
Ibn Abd al-Barr said:
“It is prohibited to shave the beard, and it is not done except by effeminate men.”[At-Tamhid]
Shafi’iyyah:
As for the Shafi’is, al-Imam ash-Shafi’i has expressed that it is prohibited to shave the beard [al-Umm]. Also, al-Athru’i said, “The correct position is that it is prohibited to totally shave the beard without a (medical) problem with it.” [Sharh ul-Ubab].
Hanabilah:
The Hanbali's agree without exception that it is prohibited to shave the beard [Al-Insaf, Sharh ul-Muntaha, etc.].
Ibn Taymiyyah stated:
“It is prohibited to shave the beard.” [Al-Ikhtiyarat ul-Ilmiyyah (p.6)]
Shaykh ul-Islam Ibn Taymiyyah said:
“Because of the authentic hadiths, it is prohibited to shave the beard, and no one has ever permitted it.”
As-Saffarini said:
“It is agreed in our mathhab that it is prohibited to shave the beard.” [Ghitha ul-Albab (1:376)].
والله يهدينا إلى الصراط المستقيم