Zechariah 12:8,9

In that day shall the Lord defend the inhabitants of Jerusalem Not only Jerusalem itself from being taken and destroyed, but all the inhabitants of it from being in any way injured: he will not only be a wall of fire about the city to fortify it, but he will compass particular persons with his favour as with a shield. The mystical Jerusalem, the Christian Church, and particularly that of the converted Jews, seems to be chiefly intended. And he that is feeble among them shall be as David The feeblest among them shall be men of war, bold and brave, skilful and strong: shall enterprise and accomplish great things, as David did, and become as serviceable to Jerusalem in guarding it as David himself was in founding and enlarging it, and as formidable as he was to the enemies of it. Observe, reader, God helps and defends his church and people by giving them courage and strength to defend and help themselves. He enables them to do their part, and then he is not wanting to do his. And the house of David shall be as God Or, as angels, as the word אלהים, Elohim, is rendered, Psalms 8:3. As the angel of the Lord before them Or, at the head of them; as that angel (so some interpret it) which went before the people of Israel through the wilderness, Exodus 23:20. God will increase the gifts and abilities, both of the people and princes, in proportion to the respective services for which they are designed. It was said of David, that he was as an angel of God, to discern good and bad, 2 Samuel 14:17; such shall now the house of David be. But this was to have its full accomplishment in Christ: now the house of David looked little and mean, and its glory was eclipsed, but in Christ the house of David was to shine more bright than ever. In him it was to become more blessed, and more a blessing than ever it had been. And l will seek to destroy all the nations, &c. See notes on Zechariah 12:3.