What is the meaning of "Ivri Artzech"?
Rashi: Go to exile.
Radak: Quickly exile yourself from your land.
What is the comparison to a river?
Rashi: [Go] like a river, which rises and spreads out. Radak - i.e. like the Nile, which leaves its place and spreads out. So you should go from your place, here and there.
Radak: Go quickly, like a river - "Ki Yavo cha'Nahar Tzar" (59:19).
Malbim: After the sea rose and flooded Tzor, it was like a river.
What is "Bas Tarshish"?
Rashi: It is Tzor, which is on the sea of Tarshish.
Radak: To the congregation of Tarshish. This is like Bas Tziyon. Also Tarshish was on the sea, near Tzor. It should say l'Sarshish; the prefix Lamed is omitted, like "va'Yavo Yerushalayim" (Melachim II, 14:13) and many similar verses.
What is the meaning of "Ein Mezach Od"?
Rashi: You have no more strength and belt to gird your loins. Mezach is an expression of an Ezor (belt) - "ul'Mezach Tamid Yachgereha" (Tehilim 109:19). Every Ezor is an expression of strength.
Radak: There is no more strength in your land.
Malbim: There is no belt to hold back the sea from coming onto the dry land; it breached its border.
