Isaiah 64:10

10.The cities of thy holiness. The Church again recounts her miseries, that she may move God to mercy and obtain pardon. She says that the cities have been reduced to “a wilderness;” and, for the sake of amplification, adds that “Zion is a desert;” because it was the royal residence, in which God wished that men should call upon him. She adds also Jerusalem, in which Zion was; for it appeared to be shameful that a city, which God had consecrated to himself, should be ruined and destroyed by enemies.

She calls them “cities of holiness,” because, as the Lord had sanctified a people, so he also wished that the cities, and even the whole country, should be consecrated to himself. Seeing, therefore, that the cities were dedicated to God, they are justly called “cities of his holiness;” for in them God reigned, and men called upon him. In the same manner we may at the present day give the appellation of “cities of God’s holiness” to those which, laying aside superstitions, worship him in a sincere and right manner.