Rashi: He will roar due to what they did to Tziyon.

Radak: His Shechinah is there, in Yerushalayim. It is as if He roars from there and puts His voice on them.

Malbim: Conduct and Mishpat come from Tziyon. Sha'agah is a great voice, the opposite of a low voice. The primary Shechinah is in Tziyon - there He will roar in a great voice.

Malbim: Nesinas Kol need not be a great voice, just it is not silent. Yerushalayim is not as Kadosh as Tziyon; there, He will not roar in a great voice, but He will not be silent. 'Giving His voice' is Divine conduct.

Rashi (from Mechilta Beshalach 2): He will exact payment from the Sarim of the nations above, and afterwards from the nations.

Radak: This is the consequence of putting His voice on them. It is a Mashal. On that day will be also noise in Eretz Yisrael, like it says in the Nevu'os of Yechezkel (38:19) and Zecharyah (14:5).

Malbim: This will result from His roaring. Conduct of nature in the land, and conduct of the Ma'arachah of Shamayim, will cease.

Rashi: It is an expression of covering; it is a shelter. Radak - He will shelter them from the nations, and from the noise, lest they harm Yisrael.

Malbim: He is a shelter for His nation, to save them from all evil.

Malbim: The name Yisrael shows that they are above nature - "Ki Sarisa Im Elohim" (Bereishis 32:29). He will be strength for them - they will overpower with His strength. This is more than a shelter!