﴿ وَمَا لَهُم بِهِۦ مِنْ عِلْمٍ ۖ إِن يَتَّبِعُونَ إِلَّا ٱلظَّنَّ ۖ وَإِنَّ ٱلظَّنَّ لَا يُغْنِى مِنَ ٱلْحَقِّ شَيْـًۭٔا ﴾

“and [since] they have no knowledge whatever thereof, they follow nothing but surmise: yet, behold, never can surmise take the place of truth.”

(And they have no knowledge thereof) they have no proof or elucidation about what they say. (They follow but a guess) they lie out of surmise and do not have any certainty, (and lo! a guess) and worship based on guess and claims based on guess (can never take the place of the Truth) cannot spare one from Allah's chastisement.