In the early years of Joash, the house of David hangs by a thread (2 Chronicles 23). Its entire future rests in a baby, Joash son of Ahaziah, whom Jehoiada the priest rescues from Athaliah’s slaughter to be raised among the priests.
By every empirical measure, the Davidic dynasty is on the ropes. It has only one thing going for it: “Yahweh has spoken concerning the son of David” that David’s descendants will reign in Jerusalem (v. 3).
The Davidic dynasty hangs by this thread – a baby and a promise. But that’s enough. The weakness of God is stronger than men.
Jehoiada trusts in this promise, but that doesn’t make him complacent and passive. He doesn’t say, “Well, if God wants the Davidic king restored, He’ll do it.”
Rather: Because the Lord has spoken, “this is the thing which you shall do” (v. 4). The Lord’s promises don’t excuse inaction. They motivate action. Jehoiada is swept up into the promise of Yahweh, and so becomes a means for its fulfillment.
And so too, we are swept up by the Spirit into the Son in whom God’s promises are Yes and Amen, and so become agents for the actualization of the promises to which we are united.