The Destruction of Evil-Till This Very Day
4.’And what He did to the army of Egypt; to its horses and to its riders, how He flooded the waters of the Reed-Sea over them as they pursued after you, and Hashem caused their destruction until this very day-וַאֲשֶׁר עָשָׂה לְחֵיל מִצְרַיִם לְסוּסָיו וּלְרִכְבּוֹ אֲשֶׁר הֵצִיף אֶת מֵי יַם סוּף עַל פְּנֵיהֶם בְּרָדְפָם אַחֲרֵיכֶם וַיְאַבְּדֵם יְהוָה עַד הַיּוֹם הַזֶּה(4240=10=1 or 9600+21 words=9621=18 counting final Pehs and Mems as 800 and 600).
The number 4240 is 10 fold the number 424:
Mashiach son of David
מָשִׁיחַ בֶּן דָּוִד
This teaches us that the destruction of all the enemies of Israel at the End of Days- "until this very day"- עַד הַיּוֹם הַזֶּה will be 10 times as powerful as the destruction of the Egyptians at the time of the Redemption from Egypt. The Torah of Mashiach will tear apart the entire world political-economic system based on lies and corruption in order to replace it with one based on Torah/Truth to the benefit of all Mankind in the Messianic era.
The words "until this very day"- עַד הַיּוֹם הַזֶּהalso teach us that the words of this passage are relevant to all times and to the time of the defeat of the enemies of Israel at the time of the Final Redemption. The words "waters of the Reed-Sea"- מֵי יַם סוּף can be understood as "waters of Jerusalem End"- מֵי י"ם סוֹף.The enemies of Israel will be destroyed when they come to wage war on Jerusalem at the End of Days.