Rabbi Roodyn

ח) שָׁמְעָה וַתִּשְׂמַח צִיּוֹן וַתָּגֵלְנָה בְּנוֹת יְהוּדָה לְמַעַן מִשְׁפָּטֶיךָ ה’:

Zion heard and rejoiced, and the daughters of Judah exulted, because of Your judgments, O Hashem.

The Radak explains this in light of the previous pesukim, that the Jewish people will rejoice when they see the full force of Hashem’s judgement on the wicked.

The Malbim explains that the essential difference between Zion and the rest of the world is in the way that Hashem interacts with it.  The land of Israel is guided by a far greater level of hashgacha than the rest of the world, being that it is the palace of the King.

Although the hashgacha of Eretz Yisrael is qualitatively different to the rest of the world and life runs according to a different set of rules, nonetheless Zion will rejoice when hearing Hashem’s judgements (namely His running of the natural world) against the wicked.

Rav Hirsch says in his initmitible way that when the One G-d will be worshipped throughout the world then joy will return to Zion, the ancient eternal capital of G-d and to the daughters of Yehuda, the desolate cities who rallied around this Sanctuary and shared its fate.

For then the One G-d Who from out of Zion caused His spirit and His Law to shape all life within the cities of Yehuda, will be recognised by all the nations as the One G-d Who rules over all things in glorious majesty.

This deliverance of all of mankind will also bring with it the resurrection of Zion and Yehuda.