These chapters start with the flrst absolute failure of David’s descendants so far as the Chronicler is concerned, Jehoram. He is influenced by his marriage into Ahab’s family and commits the same errors. But even in this, the LORD is faithful, for the sake of his promise to David. (21:7).
This doesn’t keep Jehoram from a very unpleasant death (21:18,19).
The pattern repeats itself. After a coup, the priest Jehoiada protects and guides the young king Joash, and for as long as he is there to give advice, the king acts wisely and the Kingdom prospers. When Jehoiada dies, the king turns away from the LORD’S way and disaster follows, becoming inevitable after the king sanctions the murder of the prophet Zechariah, son of Jehoiada.
In the end there is a reversal of the usual pattern. This time, when the Arameans come with a small army, the LORD is on their side, not that of Judah. And so this time it is the larger Judean army that is routed.
It’s a valuable balance to be reminded of. The LORD still holds true to his promise to David, and will not abandon Judah forever. But if she abandons the LORD, then in the short term she will be defeated. We cannot presume that we will always be favoured by God even when we fail to live by his ways. In our day, we are right to be confident that the church of God will not be defeated. But perhaps we shouldn’t be so sure that the way in which that church survives and triumphs will look anything life what we’re used to. Only by staying close to God can we be confident that we have a part in his future plans.