Then Eliezer son of Dodavahu of Mareshah prophesied against Jehoshaphat, saying, “Because you have allied yourself with Ahaziah, the LORD has destroyed your works.” So the ships were wrecked and were unable to sail to Tarshish.
We are now drawing towards the close of the history of Jehoshaphat's reign, for a further account of which those who lived when this book was published were referred to an authentic history of it, written by Jehu the prophet (Ch2 19:2), which was then extant, Ch2 20:34.
Commenting on 2 Chronicles 20:31-37
Then Eliezer the son of Dodavah of Mareshah prophesied against Jehoshaphat, saying, Because thou hast joined thyself with Ahaziah, the LORD hath broken thy works. And the ships were broken, that they were not able to go to Tarshish. (u) Thus God would not have his join in company with idolaters and wicked men.
The Lord hath broken, etc. - "The Word of the Lord hath broken." - Targum. Concerning Tarshish, Ezion-geber, and Ophir, and the voyage thither, see the notes on Kg1 10:22, and at Kg1 10:29 (note), and on Ch2 9:26-28 (note). The Tarshish here is called by the Chaldee Torsos in the great sea, some place in the Mediterranean.