According to the author of the book, this verse tells us that King Jeroboam did many strong and brave things, like fighting battles and recovering cities for Israel. All his important deeds are written in another special book about the kings.
2 Kings 14:28: Now the rest of the acts of Jeroboam, and all that he did, and his might, how he warred, and how he recovered Damascus, and Hamath, [which belonged] to Judah, for Israel, are they not written in the book of the chronicles of the kings of Israel?
Emphasizes trusting in God rather than one's own understanding, while 2 Kings 14:28 highlights achievements attributed to human effort.
Proverbs 3:5: Trust in the LORD with all thine heart; and lean not unto thine own understanding.