“When his Lord called to him in the sacred valley of Tuwa (16): ‘Go to Pharaoh; indeed, he has transgressed (17). Say, “Would you be willing to purify yourself (18), and allow me to guide you to your Lord, so that you may fear Him?” (19)’ Then he showed him the greatest sign (20).”

Allah, glorified and exalted is He, says: “It will only be one (13) cry,” meaning the final blast, “which they will hear. And then, behold, they will be upon the earth’s surface” (14)—that is, the face of the earth. In other words, they will be upon the earth’s surface after having been in its interior. (1) The Arabs call an open desert and the face of the earth sāhirah. Some linguists said: They apparently called it sāhirah because animals sleep and remain awake upon it. (2) Sufyan said: “It is the land of al-Sham.” (3) Qatadah said: “It is Hell.” (4)

Regarding His words, “Has the story of Moses reached you?” He says: The story of Moses has indeed come to you, O Muhammad. “When his Lord called to him in the sacred valley of Tuwa” (5), saying: “O Moses, go to Pharaoh; indeed, he has transgressed”—he rose in arrogance, grew haughty, and disbelieved in Allah.

“Say, ‘Would you be willing to purify yourself?’” The people of the Hijaz and Ya‘qub recited it with a doubled zāy, meaning: to purify and cleanse yourself of polytheism. The others recited it [with an undoubled zāy]. [Its original form means “to purify yourself.” In the first recitation, the second tā’ is assimilated into the zāy, whereas in the second it is omitted; its meaning is to cleanse yourself of polytheism.] (6) That is, to enter Islam and reform yourself. Ibn ‘Abbas said: “To testify that there is no god but Allah.”

“And allow me to guide you to your Lord, so that you may fear Him”—that is, I call you to worship your Lord and affirm His oneness, so that you may fear His punishment. “Then he showed him the greatest sign”: namely, the staff and the white hand.