Narrated Ibn 'Abbas: Regarding the Verse: "Verily! The worst of beasts in the Sight of Allah are the deaf and the dumb----those who understand not." (8.22) (The people referred to here) were some persons from the tribe of Bani 'Abd-Addar.
— Sahih Bukhari, Volume 6, Book 60: Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh)), Hadith #169