4. It is promised that the inhabitants of Jerusalem shall be enabled to defend themselves, and yet shall be taken under the divine protection, v. 8. See here in what method God preserves his church, and those that are his, from the gates of hell to and through the gates of heaven. (1.) He does himself secure them: In that day shall the Lord defend the inhabitants of Jerusalem, not only Jerusalem itself from being taken and destroyed, but every inhabitant of it from being any way damaged. God will not only be a wall of fire about the city, to fortify that, but he will encompass particular persons with his favour as with a shield, so that no dart of the besiegers shall touch them. (2.) He does it by giving them strength and courage to help themselves. What God works in his people by his grace contributes more to their preservation and defence than what he works for them by his providence. The God of Israel gives strength and power to his people, that they may do their part, and then he will not be wanting to do his. It is the glory of God to strengthen the weak, that most need his help, that see and own their need of it, and will be the most thankful for it. [1.] In that day the feeblest of the inhabitants of Jerusalem shall be as David, shall be men of war, as bold and brave, as skilful and strong, as David himself, shall attempt and accomplish great things, as David did, and become as serviceable to Jerusalem in guarding it as David himself was in founding it, and as formidable as he was to the enemies of it. See what divine grace does; it makes children not only men, but champions, makes weak saints to be not only good soldiers, but great soldiers, like David. And see how God often does his own work as easily and effectually, and more to his own glory, by weak and obscure instruments than by the most illustrious. [2.] The house of David shall be as God, that is, as the angel of the Lord, before them. Zerubbabel was now the top-branch of the house of David; he shall be endued with wisdom and grace for the service to which he is called, and shall go before the people as an angel, as that angel (so some think) which went before the people of Israel through the wilderness, which was God himself, Exod. xxiii. 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 Sam. xiv. 17. Such shall the house of David now be. The inhabitants of Jerusalem shall be as strong and fit for action as nature made David, and their magistrates as wise and fit for counsel as grace made him. 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 shone more brightly than ever, and its countenance was as that of an angel; in him it became more blessed, and more a blessing, than ever it had been.