The LORD was with Jehoshaphat means the LORD blessed him and protected him.
Because he walked in the earlier ways of his father: The Hebrew verb rendered walked is used figuratively with the meaning “to live” or “to behave,” as in 2 Chr 6.14 (see the comments there). Revised English Bible translates walked in the … ways as “followed the example.”
It is not clear to whom his father refers. Since Jehoshaphat’s father Asa is alluded to in verse 1, the reference may be to Asa, his biological father. However, there is a textual problem here. The most widely followed manuscript of the Masoretic Text has the name “David” here, which is the basis for those translations that read “his father David” (New International Version, Segond, Traduction œcuménique de la Bible, Reina-Valera revisada) or “his ancestor David” (Bible en français courant, Biblia Dios Habla Hoy; similarly An American Translation). This reading is widely adopted, but it is given only a {C} rating by Critique Textuelle de l’Ancien Testament. Critique Textuelle de l’Ancien Testament argues that the Septuagint probably omitted the name David because the end of the verse seems to suggest that later in his life Jehoshaphat’s father worshiped the Baals, although he had not done so earlier in his reign. Critique Textuelle de l’Ancien Testament notes the parallels between the accounts in 2 Chronicles of the reforms of Jehoshaphat and those of Josiah; and the latter refers to Josiah’s “father” (ancestor) David (2 Chr 34.2). But on the other hand, the author of 1-2 Chronicles does not elsewhere distinguish between an earlier and a later period in David’s life.
In any case, the Hebrew phrase rendered the earlier ways most likely refers to the early period of the reign of the ruler intended, whether Asa or David, and this should be expressed in translation. It is less likely that this phrase refers to the beginning of the reign of Jehoshaphat. This second interpretation is the basis for the New International Version rendering of the whole clause, which is “because in his early years he walked in the ways his father David had followed.” Good News Translation follows the first interpretation with “because he followed the example of his father’s early life.”
He did not seek the Baals: The verb seek is used here in the sense of “worship” (Good News Translation). The Hebrew word for Baals (baalim) is plural. The plural refers to various local manifestations of the god Baal. Baal was a Canaanite storm god and fertility god, whose female counterpart was sometimes Astarte and sometimes Asherah (see the comments on 2 Chr 14.3). This god was worshiped in various countries of the ancient Near Eastern world.
Quoted with permission from Omanson, Roger L. and Ellington, John E. A Handbook on 1-2 Chronicles, Volume 1. (UBS Helps for Translators). Miami: UBS, 2014. For this and other handbooks for translators see here .