The hadith relate that the Mahdi's brow will be clear and broad, and that his head will be proportionately large.
The Mahdi is one of my people ... His brow is open.
(Al-Muttaqi al-Hindi, Al-Burhan fi Alamat, p. 21)
The Mahdi is one of us, and his brow is open... (Al-Muttaqi al-Hindi, Al-Burhan fi Alamat., p. 21)
Allah will send a son of my line, with a clear brow, who will fill Earth with justice and distribute goods and property in abundance.
(al-Haythami, Al-Qawl al-Mukhtasar, p .23)
He is broad of brow. (Fera Idu Fevaidi'l Fiqr)
Allah will send one of my lines who is brad of brow.
(Fera Idu Fevaidi'l Fiqr, p. 11)