This is their answer to Prophet Hud (PBUH). We notice that Allah (swt) adds the act of disbelief to the eminent ones of the Prophet Hud (PBUH), yet He (swt) does not do that while speaking about the people of Noah (PBUH). That is because among the people of A’d there was believers from the time of Prophet Noah (PBUH). As for the Prophet Noah (PBUH), there was no one amongst his people who had attained faith.
( إِنَّا لَنَرَاكَ فِي سَفَاهَةٍ ) (and indeed, we think you are of the liars): The people of Prophet Noah (PBUH) told him: (“Indeed, we see you in clear error.”). The difference here is that (to be in clear error) refers to being in falsehood, it is avoiding the truth. Whereas to be a liar is out of recklessness and ignorance. They were thus claiming that Prophet Hud (PBUH) was reckless and ignorant.