Jubair bin Nufair Hadhrami narrated that the Messenger of Allah (peace be upon him) said: "Messengers have come to you who are neither weak nor lazy, so that they may awaken the heedless and veiled hearts, enlighten blind eyes, make deaf ears hear, and straighten crooked peoples and communities, until it is said «لا اله الا الله» that there is no deity except Allah."