What do ye imagine— Why do ye take counsel? &c. The prophet says this to the Ninevites, who seemed willing to repair the loss of Senacherib's army, and to invade Judaea; and it is most likely, says Houbigant, that Nahum, when he delivered this prediction, was a captive in Nineveh, as was Tobias, or in some neighbouring place.
Related Commentaries of Nahum 1:9
9 What do ye imagine against the LORD? he will make an utter end: affliction shall not rise up the second time.