Surah 26. Ash-Shuara, Ayah 44

The reason for their premature sense of triumph is given in 7:116 ("they cast a spell upon the people’s eyes, and struck them with awe") and {20:66-67} ("by virtue of their sorcery, their [magic] ropes and staffs seemed to him to be moving rapidly; and in his heart, Moses became apprehensive").

Though Pharaoh claimed to be a god. And so they appeal to his "divine" power.