the "Lying Spirit"

... or, "who you gonna believe?"

Here is the core of the text in question, and one possible reading of it, up until Micheas breaks the spell. The end of the story is that Achab is told plainly that he will be overthrown in battle, Achab goes forth to battle, and there is overthrown.

Enter Micheas, enter nunzio

13 And the messenger, that went to call Micheas, spoke to him, saying: Behold the words of the prophets with one mouth declare good things to the king: let thy word therefore be like to theirs, and speak that which is good. 14 But Micheas said to him: As the Lord liveth, whatsoever the Lord shall say to me, that will I speak.

Exeunt, et introibunt ad regem

15 So he came to the king, and the king said to him: Micheas, shall we go to Ramoth Galaad to battle, or shall we forbear? He answered him: Go up, and prosper, and the Lord shall deliver it into the king's hands.

... and who told him to say that? Was it the Lord? Assuredly not, for recall: "the messenger [] spoke to him : '[] let thy word be like to theirs...'"; perhaps Micheas is speaking sardonically, perhaps he is so far nonplussed at being consulted over the King's own advisors, when he certainly already knows that the King likes him not; we don't know, but the King does not believe him. If Micheas is lying, he's not very good at it!

16 But the king said to him: I adjure thee again and again, that thou tell me nothing but that which is true in the name of the Lord. 17 And he said: I saw all Israel scattered upon the hills, like sheep that have no shepherd: and the Lord said: These have no master: let every man of them return to his house in peace.

Only now has Micheas begun to speak in prophetic register. Achab repeats his hesitation --- the one from before I started quoting --- before Micheas continues in parable

18 (Then the king of Israel said to Josaphat: Did I not tell thee, that he prophesieth no good to me, but always evil?) 19 And [Micheas] added and said: Hear thou therefore the word of the Lord:

I saw the Lord sitting on his throne, and all the army of heaven standing by him on the right hand and on the left: 20 And the Lord said: Who shall deceive Achab king of Israel, that he may go up, and fall at Ramoth Galaad? And one spoke words of this manner, and another otherwise. 21 And there came forth a spirit, and stood before the Lord, and said: I will deceive him. And the Lord said to him: By what means? 22 And he said: I will go forth, and be a lying spirit in the mouth of all his prophets. And the Lord said: Thou shalt deceive him, and shalt prevail: go forth, and do so.

The whole picture of celestial intrigue is what God told Micheas to relate, which is how you can tell that it's not a superficially-literal narrative. To whom is Micheas speaking? To Achab. Who has deceived Achab? Achab himself. For now he has heard his "prophets" speak encouragement, and Micheas speak of his downfall, and warn him that his "prophets" have spoken lies, yet which does he choose to heed? If the tale Micheas tells of the lying spirit before the Lord is superficially true, if the literal meaning of this scripture is a celestial conspiracy against Achab, then what can be the purpose of the Lord's own prophet revealing it before the trap is closed? Rather, it is a parable, imploring Achab to humility, warning that he has surrounded himself by liars and sycophants, that if he go up to Ramoth Galaad it is the Lord Himself will defeat him.

And Achab goes up to Ramoth, not because he has been deceived by any extraordinary act of God, but because God has told him the truth and Achab has despised it.