His oneness—from the rising and setting of the sun, the appearance and disappearance of the moon, and the appearance and setting of the stars. Then he said: “Unless my Lord guides me, I will surely be among those who are astray.” [al-An‘am: 77] Thus it was known that guidance is attained through transmitted revelation. Likewise, knowledge of the Messengers must be acquired through transmitted revelation.

Allah, Most High, says: “Say, ‘O mankind! I am Allah’s Messenger to you all—He to whom belongs the dominion of the heavens and the earth. There is no god worthy of worship except Him. He gives life and causes death. So believe in Allah and His Messenger, the unlettered Prophet, who believes in Allah and His words, and follow him so that you may be guided.’”

And the Most High says: “We would never punish until We have sent a messenger.” [al-Isra'