יְהוָ֖ה יִלָּחֵ֣ם לָכֶ֑ם וְאַתֶּ֖ם תַּחֲרִישֽׁוּן׃ (פ)
«永恆者必為你們爭戰,你們只管靜默不言。»
Rashi
ילחם לכם means He will fight on your behalf; similar is (v. 25) “For the Lord fighteth for them (להם)”; so too, (Job. 13:8) “will ye contend for God (לאל)?” and thus, too, (Genesis 24:7) “and who spoke on my behalf (לי)”, and so, too, (Judges 6:31) “Will ye plead for Baal (לבעל)?”
Or HaChaim
ה׳ ילחם לכם, "G'd will fight on your behalf, etc." Inasmuch as the reason the Israelites had been frightened had been that they saw themselves confronting celestial forces, G'd tells them that the most powerful celestial force, He Himself, will fight on their behalf. When G'd is involved personally, even a thousand celestial forces equal to the guardian angel of Egypt are nothing to be afraid of.
Rabbeinu Bahya
ה' ילחם לכם, “Hashem will fight on your behalf!” It is known in kabbalistic circles that the attribute of Justice fights wars and dries out the sea. Why then did Moses mention the attribute Hashem in this verse? It was to teach that even in the execution of this great miracle the attribute of Hashem was also involved. At first glance it appears as if the attribute of Justice was stretched out over the Egyptians from one end of the sky to the other (figuratively speaking) and was bent on their total destruction as we know from verse 28 that “not one of them survived.” Nonetheless we find an involvement of the attribute of Mercy such as the fact that these people were interred (compare 15,12 תבלעמו ארץ), i.e. that the earth covered their remains. They did not simply disintegrate as did the people who died during the deluge.” Whenever the Torah speaks of G’d’s “right hand,” such as in Exodus 15,6 this is a reference to the attribute of Mercy. What was true in the past will also hold true in the future after the final war of Gog and Magog of which we are told that “G’d goes out and battles all these nations assembled against the Jewish people” (compare Zecharyah 14,3). No doubt that verse speaks of the attribute of Justice. In spite of this, we find even there an involvement of the attribute of Mercy as the prophet describes in detail the interment of the remains of the fallen Gentiles in that war (Ezekiel 39,11). “It will be on that day that I (Hashem) shall assign to Gog a burial, etc. etc.”