Jerusalem will be a sanctuary, and strangers will not pass through it any more. In the beginning of this verse Jehovah promises to be the God of his people; he points to the place of his abode, and purifies Jerusalem by judgment that it will be a true holy place, untrodden by the foot of Gentile stranger or Jewish unbeliever any more.
His people would recognize his presence and his power by the wonderful deliverance vouchsafed to them. "Jerusalem," says Kimchi, "shall be a sanctuary, like the sanctuary which was forbidden to strangers; and strangers shall not pass through it any more to do injury to them as they have done up to this day.
It may also be explained that strangers shall not enter into Jerusalem, for its holiness shall be great for the future. And as the temple was forbidden even for Israel to enter there, so all the city shall be a sanctuary into which strangers out of the nations of the world shall not enter."