folly," meaning: in judgment, "and we surely think you are among the liars." Their denial of him was based on conjecture.
سفاهةٍ﴾ أَيْ: مِنَ الرَّأْيِ ﴿وَإِنَّا لَنَظُنُّكَ من الْكَاذِبين﴾ كَانَ تكذيبهم إِيَّاه بِالظَّنِّ.