﴿ وَأَنَّهُۥ كَانَ يَقُولُ سَفِيهُنَا عَلَى ٱللَّهِ شَطَطًۭا ﴾

“"'And [now we know] that the foolish among us were wont to say outrageous things about God,”

(And that the foolish one among us) i.e. the devil (used to speak concerning Allah an atrocious lie.