בַּיּ֣וֹם הַה֡וּא יִפְקֹ֣ד יְהוָה֩ בְּחַרְב֨וֹ הַקָּשָׁ֜ה וְהַגְּדוֹלָ֣ה וְהַֽחֲזָקָ֗ה עַ֤ל לִוְיָתָן֙ נָחָ֣שׁ בָּרִ֔חַ וְעַל֙ לִוְיָתָ֔ן נָחָ֖שׁ עֲקַלָּת֑וֹן וְהָרַ֥ג אֶת־הַתַּנִּ֖ין אֲשֶׁ֥ר בַּיָּֽם׃ (ס)
En ce jour, l’Éternel châtiera de sa forte, grande et puissante épée le léviathan, serpent droit comme une barre, et le léviathan, serpent aux replis tortueux; il fera périr aussi le monstre qui habite la mer.
Rashi
on leviathan the barlike serpent Jonathan renders: On the king who aggrandized himself like Pharaoh the first king, and upon a king who was as haughty as Sennacherib the second king. בָּרִיחַ is an expression of ‘straight’ like a bar, since he is the first. (The matter of simplicity is related to oneness. Since Pharaoh was the first great king, he is referred to as ‘the barlike serpent,’ a straight, penetrating serpent, that does not coil.)
Ibn Ezra
ביום ההוא In those days.1ביום ההוא Though singular, does not refer to one particular day, but to a whole period.
Rashi
crooked An expression of ‘double,’ since he is the second one. (I.e. the bend in the serpent indicates duality, thus the number two.) And I say that these are three important nations: Egypt, Assyria, and Edom. He, therefore, stated concerning these as he said at the end of the section (v. 13), “And those lost in the land of Assyria shall come, as well as those lost in the land of Egypt,” and since the nations are likened to serpents that bite.
Rashi
and He shall slay the dragon that is in the sea That is Tzor that is the head of the children of Esau, and it is situated in the heart of the seas, and so Kittim are called the islands of the sea, and they are the Romans [according to certain manuscripts]. ([Some editions read:] They are the Greeks.)