“But my Lord has commanded me to let my beard grow and to trim my mustache.” [Hasan]

So you—yes, you, the clean-shaven one—how will you feel if the Messenger of Allah ﷺ is pained at the sight of your face? Indeed, what answer will you give if he turns away from you with his noble countenance, saying:

“Woe to you! Who ordered you to do that?!”

Letting the Beard Grow Is an Innate Human Disposition

Allah the Exalted says, “So set your face toward the religion in pure devotion—the innate disposition of Allah upon which He created humankind; let there be no change in the creation of Allah…” ⦗al-Rum 30:30⦘.

Meaning: Direct yourself and remain steadfast upon the religion Allah has prescribed for you—the pure monotheism of Abraham—while at the same time adhering to your sound innate disposition (fitrah) that Allah has implanted in His creatures: recognizing Him, affirming His oneness, and all that follows from that among the traits of the fitrah.

ʿĀʾishah reported that the Messenger of Allah ﷺ said, “Ten acts belong to the fitrah: trimming the mustache, letting the beard grow, using the tooth-stick, inhaling water into the nose, cutting the nails, washing the knuckles, plucking the armpit hair, shaving the pubic hair, and cleaning oneself with water.”