Bob Becking discusses the background to Micah 3:12.
Bob Becking, Micah: A New Translation with Introduction and Commentary (Anchor Yale Bible 24I; New Haven: Yale University Press, 2023), 149, 153-54
The section culminates in a prophecy of doom for Zion and Jerusalem, which will be destroyed by an unknown enemy (3:12). It is this verse that is said to have saved the life of the prophet Jeremiah. When he was accused of being too negative a prophet, some of the leaders proclaimed that Micah had been a prophet of doom too and was not killed by Hezekiah, the king of Judah (Jer. 26:18-19). In their quotation of Mic 3:12, the friends of Jeremiah place the prophecy of doom in the reign of Hezekiah. This has led to a discussion on the exact date and circumstances in which Micah would have given this prophecy. Taking the campaign of Sennacherib against Hezekiah in 701 BCE as a context is certainly a possibility (see Andersen and Freedman 2000, 386-87). That campaign, however, was not the only moment of threat to the independence of Jerusalem.
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The whole of Micah 3 ends with a fierce prophecy of doom. Once more, the leading elite in Judah are reproached for their breaking of the social and religious codes of ancient Israel and for their lack of responsibility in a time of crisis (Zimran 2021). The people in charge are condemned because they value money as a central item in their mindscape (Arena 2020, 159). Even the word of God has its price on the free market. In thinking and acting this way, they build Jerusalem with blood and not upon the foundation of justice (see also R. L. Smith 1984, 3435; Gignilliat 2019, 140-47).
This judgment will be a catastrophe. The beautiful city and its temple mount will be ruined and turned into pieces of land that can be plowed (not into an undesirable wilderness; contra Bail 2004, 32-38). Ironically, the author uses words for this shift that echo the language of haughtiness to be found in Neo-Assyrian royal inscriptions in the description of the fate of the capital city of a disloyal vassal.
There is more at stake than human pride, which will have its fall. Micah criticizes the economic system of his days in which the elite act as if there is no moral code. This acting with God between brackets is still very common.