{Say, "Travel through the land and observe how was the end of those before."}

This is presented to emphasize that disobedience causes the wrath and punishment of Allah the Exalted. They were commanded to travel and observe how Allah the Exalted destroyed nations and made them taste an evil end due to their sins, so that they may confirm the truth of what has preceded.

His saying, {“Most of them were polytheists”}, is a resumption [of speech] to indicate that polytheism alone was not the cause for the destruction of all of them; rather, it is the cause for destruction in the majority of them, while other sins are the cause for it in a minority.

It is also permissible that it serves to indicate that their evil end was due to the prevalence and dominance of polytheism among them; thus, it contains an alarming depiction of the gravity of polytheism, as it is a trial that does not afflict only those who have wronged themselves.