Charles Ellicott Commentary 2 Chronicles 18:9

"Now the king of Israel and Jehoshaphat the king of Judah sat each on his throne, arrayed in their robes, and they were sitting in an open place at the entrance of the gate of Samaria; and all the prophets were prophesying before them." — 2 Chronicles 18:9 (ASV)

And the king of Israel ... sat either of them on his throne. —Rather, Now the king of Israel ... were sitting each on his throne.

Clothed in their robes. —The pronoun, which is indispensable if this is the meaning, is missing in the Hebrew. The Syriac has probably preserved the original reading: Clothed in raiment spotted white and black. (See below.)

And they sat. —Were sitting. Explanatory addition by chronicler.

A void place. — A threshingfloor. Septuagint, ἐν τῷ εὐρυχώρῳ, in the open ground; Vulgate, in a threshing floor. The word is probably corrupt, and may have originated out of bĕruddîm, i.e., perhaps embroidered; an epithet of robes.

Prophesied. — Were prophesying. “Vaticinabantur,” Vulgate.