Why are the rivers clamoring?
Rashi: They scream and complain. The nations who flood like rivers raised their voice, and the depth of their sources they raise to be haughty against You.
Radak: 'Rivers' is a metaphor for Gog and Magog and the kings with him who will gather against Yerushalayim. They will clamor like strong rives that flow noisily - "k'Kol Mayim Rabim" (Yechezkel 1:24). Also Melech Ashur is compared to a river - "Hineni Ma'aleh Aleihem Es Mei ha'Nahar ha'Atzumim veha'Rabim" (Yeshayah 8:7). They raise their voices and the breakage of Yisrael.
Malbim: They say "Nachon Kis'acha me'Az me'Olam Atah." They testify that Hashem conducts nature, His Kisei, from of old, and He also conducts with Hashgachah - "la'Shem ha'Aretz u'Melo'ah...; "Ki Hu Al Yamim Yesadah v'Al Naharos Yechoneneha" (Tehilim 24:1-2). From the seas and rivers we know that la'Shem ha'Aretz. Water's nature is to cover the land. Hashem gave to it a different nature, to gather to one place and the dry land will be seen. Rivers cause the land to be inhabited and water will be found everywhere to water grain fields and for living beings to drink. Their voice (like the sea's) testifies that His Kisei was of old. Also refer to 93:3:2:3.
What is "Dachyam"?
Rashi: Every Dach is an expression of depth and lowliness.
Radak: It is breakage, like "Tagelenah Atzamos Dikisa" (51:10), "Ki Dikisanu bi'Mkom Tanim" (44:20).
Malbim: It is not where rivers flow strongly, rather, where they were pressed to the borders of the land and their rapid flow ceased, to enable settlement. This testifies that Hashem's Hashgachah fills the land 1 .
I understand this only if their flow changed according to a need, e.g. after Yisrael entered the land, but not if they always flowed like this! (PF)
