وَما لَهُم بِهِ مِن عِلمٍ ۖ إِن يَتَّبِعونَ إِلَّا الظَّنَّ ۖ وَإِنَّ الظَّنَّ لا يُغني مِنَ الحَقِّ شَيئًا

They do not have any knowledge of that. They follow nothing but conjectures, and indeed conjecture is no substitute for the truth.

EXEGESIS

Ḥaqq (truth) is that which a thing really is. To say that something is ḥaqq means we should have knowledge of it in a way that does not allow for that knowledge to be contradicted and later proven false. What God demands from us is that we follow knowledge, not conjecture: Do not follow that of which you have no knowledge (17:36). As we briefly mentioned earlier (see the commentary on verse 23), those principles in the shariah that allow us to act on other than certainty are exceptions based on separate evidence that qualify the absoluteness of this verse. As for matters of belief, they are still encompassed by this verse.^{‎[1]Mizan, 19/40-41.} In brief, no one should base their religion and ideology on conjecture, but rather on evidence, reasoning, and knowledge.

EXPOSITION

This verse is a restatement of what was said in verse 23, in which there was the addition of the desires of the [lower] soul, which is not repeated here. What was understood from that verse is that their conjectures were not based on evidence or sound reasoning, but rather their desires. Hence, their conjecture here is referring to false suppositions. Naturally, such false suppositions can never be a substitute for the truth.

[1] Mizan, 19/40-41.