The confrontation with Ahab
According to 1 Kings 22 and 2 Chronicles 18, Jehoshaphat, king of Judah, joined Ahab, king of Israel, who proposed a joint campaign to recover Ramoth-gilead from Aramean control. Ahab's four hundred prophets unanimously endorsed the expedition, but Jehoshaphat asked whether there was a further prophet of the Lord to be consulted. Ahab reluctantly named Micaiah, son of Imlah, saying that he disliked him because his prophecies had never been favorable to the king.
When first brought before the kings, Micaiah echoed the assurance of the court prophets, but Ahab pressed him to speak the truth in the name of the Lord. Micaiah then delivered his genuine prophecy, describing a vision of the heavenly council in which the Lord sought one who would entice Ahab to go up to the battle in which he would fall. A spirit came forward and offered to become a lying spirit in the mouth of the prophets, accounting for the unanimous and false counsel Ahab had received.
Opposition and imprisonment
Zedekiah, son of Chenaanah, the leader of the four hundred prophets, struck Micaiah and insisted that the Lord spoke through himself rather than through Micaiah. Ahab ordered Micaiah imprisoned and sustained on bread and water until the king should return from the campaign in peace.
The narrative reports that Ahab nonetheless went up to Ramoth-gilead and died in the battle, which the biblical text presents as the fulfillment of Micaiah's word. The episode has long been read as an example of the prophet who speaks the truth at personal cost against the pressure of a royal court and a majority of false prophets.
Commemoration among the Forefathers
In the Orthodox Church Micaiah is commemorated on December 14 and is reckoned among the Holy Forefathers. The Sunday of the Forefathers, which falls between December 11 and 17 within the Nativity Fast, honors the ancestors of Christ according to the flesh and the prophets and righteous of the Old Testament, from Adam to Joseph the Betrothed, including those named in the genealogy of Luke 3:23-38.
This commemoration sets the prophets within the long preparation, embodied in the history of Israel, for the coming of the Messiah. As one of the prophets of that era, Micaiah is numbered among those whose witness the Church remembers as the Nativity of Christ draws near.