Surah An-Najm 53:28

وَمَا لَهُم بِهِۦ مِنْ عِلْمٍ ۖ إِن يَتَّبِعُونَ إِلَّا ٱلظَّنَّ ۖ وَإِنَّ ٱلظَّنَّ لَا يُغْنِى مِنَ ٱلْحَقِّ شَيْـًٔا

And they have thereof no knowledge. They follow not except assumption, and indeed, assumption avails not against the truth at all.

Translation: Saheeh International

Tafsir

But they do not have any knowledge thereof of this claim. They follow in this respect nothing but conjecture which they have conjured up and indeed conjecture can never substitute for the truth that is to say when it comes to acquiring knowledge of that which one is required to have knowledge of.

Excerpt from Tafsir al-Jalalayn, commentary on 53:28, via Quran.com. The reader has the full commentary and 9 more tafsirs.