All right, now that we’re not calling down the demons of Hell upon ourselves, and trying to fill the concentration camps again, let’s talk about Ezekiel 37 and the Valley of Dry Bones.
Well, obviously the first fulfillment of this was when Israel came back from Babylon. That’s the one that Ezekiel was most concerned with, at the time.
The second fulfillment was in Matt. 27: 52, when “many of the saints” got up out of their graves and walked around Jerusalem, after Jesus went down to Sheol and brought out the patriarchs and holy people of the past. Literally, “The Word of the Lord” spoke to their bones, and they got up and lived. It was a sign of greater stuff to come, and the rest of Ezekiel’s prophecies being still in force. (Which is what the Book of Revelation gets into, along with tying Daniel and other prophets to the Gospel.)
The third fulfillment is probably the foundation of the State of Israel, although I don’t insist upon it, and there have probably been plenty of other minor fulfillments along the years.
Of course the most important fulfillment is the one that has not yet come – when the General Resurrection brings all the dead out of their graves. We know there will be a New Jerusalem on the new earth, and we know that countless numbers of people from the various tribes of Israel will be among the blessed.
Finally, I would point out a Jewish legal point that Scott Hahn is very big about. You can break the terms of a covenant as much as you like, but you are still part of that covenant. Breaking the terms triggers covenant curses, but it doesn’t end the covenant like it would end some kinds of contract.
So no matter how much Israel disobeys, their covenant with God does not end. Jesus has taken the covenant curses upon Himself, and further, He has improved the New Covenant for all who will take it. But God’s covenant is still there, because God and covenants do not have takebacks.
As for the OP’s last question –
Jesus is our “David,” because He is the head of the House of David. He has been King of Israel and King of the Jews since He was born. He reigns over Israel now and forever, as well as over the whole universe. His kingdom will never end. He fulfills God’s promise to David, and Ezekiel’s prophecies, as well as all the other royal messianic prophecies.