Section: On Ibn Hazm’s Statement of Consensus that Trimming the Mustache and Growing the Beard is Obligatory
Ibn Hazm records a consensus that trimming the mustache and letting the beard grow is an obligation. His citation of this agreement is the most decisive answer to anyone who claims that the beard has nothing to do with Islam.
Abu ‘Umar Ibn ‘Abd al-Barr and Shaykh al-Islam Ibn Taymiyyah both declared that shaving the beard is unlawful. Ibn ‘Abd al-Barr added, “No one does that except effeminate men.” Effeminate men are those who imitate women.
Imam Ahmad transmitted with a sound chain from Abu Hurayrah (may Allah be pleased with him) that the Messenger of Allah, peace and blessings be upon him, “cursed the effeminate men who imitate women and the masculinised women who imitate men.” He likewise reported from ‘Abd Allah ibn ‘Amr (may Allah be pleased with them both) that he heard the Messenger of Allah, peace and blessings be upon him, say, “Whoever among women imitates men, and whoever among men imitates women, is not one of us.”
There are many hadiths that curse men who imitate women and women who imitate men.