The Not So Great Sea
(כא) וַיֵּ֨ט מֹשֶׁ֣ה אֶת־יָדוֹ֮ עַל־הַיָּם֒ וַיּ֣וֹלֶךְ ה' ׀ אֶת־הַ֠יָּ֠ם בְּר֨וּחַ קָדִ֤ים עַזָּה֙ כׇּל־הַלַּ֔יְלָה וַיָּ֥שֶׂם אֶת־הַיָּ֖ם לֶחָרָבָ֑ה וַיִּבָּקְע֖וּ הַמָּֽיִם׃
(21) Then Moses held out his arm over the sea and ה' drove back the sea with a strong east wind all that night, and turned the sea into dry ground. The waters were split,

וְאַתָּה הָרֵם אֶת מַטְךָ, מִיָּד שָׁמַע משֶׁה לְהַקָּדוֹשׁ בָּרוּךְ הוּא וְהָלַךְ לִקְרֹעַ הַיָּם, וְכֵיוָן שֶׁהָלַךְ לִקְרֹעַ אֶת הַיָּם, לֹא קִבֵּל עָלָיו לְהִקָּרֵעַ, אָמַר לוֹ הַיָּם, מִפָּנֶיךָ אֲנִי נִקְרַע, אֲנִי גָּדוֹל מִמְּךָ, שֶׁאֲנִי נִבְרֵאתִי בַּשְּׁלִישִׁי וְאַתָּה נִבְרֵאתָ בַּשִּׁשִּׁי. כֵּיוָן שֶׁשָּׁמַע משֶׁה כָּךְ הָלַךְ וְאָמַר לְהַקָּדוֹשׁ בָּרוּךְ הוּא אֵין הַיָּם רוֹצֶה לְהִקָּרֵעַ, מֶה עָשָׂה הַקָּדוֹשׁ בָּרוּךְ הוּא נָתַן יְמִינוֹ עַל יְמִינוֹ שֶׁל משֶׁה, שֶׁנֶּאֱמַר (ישעיה סג, יב): מוֹלִיךְ לִימִין משֶׁה וגו'. מִיָּד כֵּיוָן שֶׁהֵרִים משֶׁה יָדוֹ עַל הַיָּם, נִבְקַע, שֶׁנֶּאֱמַר (שמות יד, כא): וַיִּבָּקְעוּ הַמָּיִם, אֵינוֹ אוֹמֵר וַיִּבָּקַע הַיָּם, אֶלָּא וַיִּבָּקְעוּ הַמָּיִם, מְלַמֵּד שֶׁכָּל הַמַּיִם שֶׁהָיוּ בְּכָל הַמַּעְיָינוֹת וּבַבּוֹרוֹת וּבְכָל מָקוֹם, נִבְקְעוּ, שֶׁנֶּאֱמַר: וַיִּבָּקְעוּ הַמָּיִם, וְכֵן בְּשָׁעָה שֶׁחָזְרוּ חָזְרוּ כָּל הַמַּיִם, שֶׁכֵּן הוּא אוֹמֵר (שמות יד, כח): וַיָּשֻׁבוּ הַמַּיִם, וְכָל הַנִּסִּים הַלָּלוּ נַעֲשׂוּ עַל יְדֵי משֶׁה, שֶׁנֶּאֱמַר (שמות יד, כא): וַיֵּט משֶׁה אֶת יָדוֹ עַל הַיָּם, לְפִיכָךְ הַקָּדוֹשׁ בָּרוּךְ הוּא מְשַׁבְּחוֹ, שֶׁנֶּאֱמַר (ישעיה סג, יא): וַיִּזְכֹּר יְמֵי עוֹלָם משֶׁה עַמּוֹ, וּכְתִיב (ישעיה סג, יב): מוֹלִיךְ לִימִין משֶׁה זְרוֹעַ תִּפְאַרְתּוֹ:

"And you, raise your staff" (Exodus 14:15) Moses listened to God and went to split the sea, but when he went to divide the sea, it would not accept from him to split. The sea said to him, "I should split before you? I am greater than you! I was created on the third day, and you were created on the sixth day!" When Moses heard this, he went and said to the Holy One , "The sea doesn't want to be split." What did the Holy One do? God placed God's right hand on the the right hand of Moses, as it is said, "who caused [God's glorious arm] to go at the right hand of Moses [dividing the waters before them to make Godself an eternal name]" (Isaiah 63:12) Immediately when Moses raised his hand against the sea, it was split, as was said, "The waters split" (Exodus 14:21). It does not say, the sea split, but rather the waters split to teach that all the waters that were in all the springs, and the well and in every place were split, as was said, "The waters were split." And so, at the time that they returned, all the waters returned, for such it says, "And the waters returned" (Exodus 14:28). And all these miracles were done through the hand of Moses, as was said, "And Moses extended his hand over the sea" (Exodus 14:21). Therefore, the Holy One Blessed Be He praised him, as was said, "His people remembered the days of old - Moses" (Isaiah 63:11), and it is written [in the next verse]: "who caused [His glorious arm] to go at the right hand of Moses".

Kedushat Levi, Exodus, Beshalach 2
Exodus 14,21. “Moses inclined his hand ‎above the sea, etc;” there is a statement in ‎‎Sh’mot Rabbah 21,6 according to which Moses ‎commanded the sea in the name of God to divide itself ‎so as to let the Israelites march through; the sea ‎demurred, saying to him: “son of Amram, I am greater ‎than you, etc.,’”‎
Naturally, the Midrash is an allegory, but ‎we must understand what the author of the ‎‎Midrash is trying to convey to us. God has ‎assigned nature its tasks in broad outlines, and one of ‎the rules by which the sea is governed is to perform its ‎task loyally. In the course of the thousands of years ‎that nature performs its task, which is mostly to act as ‎an agent of God’s largesse for the benefit of mankind, ‎nature tends to forget that what it does is no more ‎than to carry out the will of the Creator, and it begins ‎to think of itself as an independent, sovereign force. ‎When the Creator becomes aware of this, they decide to ‎remind nature that they are the “boss,” and that had it not been for God, nature would be completely impotent. If ‎at the time when Moses addressed the sea in the name ‎of God, the sea would have responded immediately, it ‎would not have had to humble itself beyond a ‎minimum and have to be turned into dry land, as it did ‎after having insisted that seeing it had been created on ‎the third day of creation whereas man was only created ‎on the sixth day, man had no authority to issue orders ‎to it even in the name of the Creator.
According to the midrash, (Sh’mot ‎Rabbah 23,14) the opening line in Moses’ ‎שירת הים‎, ‎Song of thanksgiving after the crossing of the sea, ‎‎(Exodus 15,1) which contains the words: ‎כי גאה גאה‎, “For ‎God is highly exalted,” was inspired by the haughty ‎response the sea had used to deny Moses’ initial ‎command to divide its waters to permit the Israelites to ‎cross. This is also alluded to in Exodus 14,21 ‎ויולך ה' את ‏הים ברוח קדים עזה כל הלילה וגו'‏‎, “Hashem made the ‎sea travel all night long driven by a strong easterly ‎wind, etc;” this was the punishment for the sea that ‎had boasted to Moses that it considered itself as ‎greater than he. The expression ‎עזה‎ instead of ‎חזק‎ ‎which would be the customary word used for a “strong” ‎wind, suggests that the sea was being repaid measure ‎for measure for its arrogance. Due to God making use ‎of this strong easterly wind, the sea was forced not ‎only to split, but to turn its bed into dry land. God ‎wished to prove to the sea how quickly it could be ‎turned into its very opposite. The “greater” something ‎in this material world of ours, the easier and the more ‎utterly can it be destroyed with one fell swoop.‎