Divrey Hayamim Bais 20:35

35 And after this did Yehoshaphat Melech Yehudah join himself in alliance with Achazyah Melech Yisroel, who did very wickedly;

Divrey Hayamim Bais 20:35 Meaning and Commentary

2 Chronicles 20:35

And after this did Jehoshaphat king of Judah join himself with
Ahaziah king of Israel
Meaning, not after the invasion of the Moabites and the slaughter of them, but after Jehoshaphat returned from Ramothgilead, when he was reproved by a prophet for helping the ungodly, ( 2 Chronicles 19:1 2 Chronicles 19:2 ) so that it was a great aggravation of his folly and weakness, that after that, and quickly after that, he should join himself to a wicked prince, though not in war, but in trade; for so it must be, since Ahaziah reigned but two years, and those not complete, see ( 1 Kings 22:51 ) , but is here related, that Jehoshaphat's weaknesses and blemishes might be laid together:

who did very wickedly;
that is, Ahaziah, who walked in the ways of Ahab his father, and of Jezebel his mother, and of Jeroboam the son of Nebat, ( 1 Kings 22:52 ) .

Divrey Hayamim Bais 20:35 In-Context

33 Howbeit the high places were not removed; for HaAm as yet had not set their hearts unto Elohei Avoteihem.

34 Now the rest of the acts of Yehoshaphat, harishonim and ha’acharonim, hinei, they are written in the Annals of Yehu ben Chanani, who is recorded in the Sefer of the Melachim of Yisroel.

35 And after this did Yehoshaphat Melech Yehudah join himself in alliance with Achazyah Melech Yisroel, who did very wickedly;

36 And he joined himself with him to make oniyot (ships) to go to Tarshish, and they made the oniyot in Etzyon-Gever.

37 Then Eliezer ben Dodavahu of Mareshah prophesied against Yehoshaphat, saying, Because thou hast joined thyself in alliance with Achazyahu, Hashem hath wrecked thy ma’asim. And the oniyot were wrecked, that they were not able to sail to Tarshish. [T.N. Yehoshaphat had a weakness for entangling himself with non-believers and suffering the consequences.]