﴿ أَسْبَٰبَ ٱلسَّمَٰوَٰتِ فَأَطَّلِعَ إِلَىٰٓ إِلَٰهِ مُوسَىٰ وَإِنِّى لَأَظُنُّهُۥ كَٰذِبًۭا ۚ وَكَذَٰلِكَ زُيِّنَ لِفِرْعَوْنَ سُوٓءُ عَمَلِهِۦ وَصُدَّ عَنِ ٱلسَّبِيلِ ۚ وَمَا كَيْدُ فِرْعَوْنَ إِلَّا فِى تَبَابٍۢ ﴾

“the means of approach to the heavens - and that [thus] I may have a look at the god of Moses: for, behold, I am indeed certain that he is a liar!” And thus, goodly seemed unto Pharaoh the evil of his own doings, and so he was barred from the path [of truth]: and Pharaoh’s guile did not lead to aught but ruin.”

What Pharaoh said to his minister, Haman, was not said seriously, but by way of a timely stratagem. He saw that the cogent and reasonable words of the true believer were having an effect on the people. So, he wanted to raise a frivolous point in order that Moses’ call should not become the topic of serious discussion but appear rather as a mere triviality.