by Rabbi Avigdor Miller
"AND HASHEM TURNED BACK THE SEA BY A STRONG EAST-WIND ALL THE NIGHT." (Shemos 14:2 1)
The wind was entirely unnecessary, for it was naturally unable to split the sea open and create a pathway, as the verse concludes "And it made the sea into dry land and the waters were split apart." This was entirely a miracle, which resulted when "Moshe stretched out his arm over the sea" as Hashem had commanded him (14:16).
But two factors participated in this arrangement:
All of Nature was in turmoil, for a reason
1) Egypt was misled into believing that the splitting of the sea could be attributed to the strong east-wind, and therefore they did not hesitate to enter between the two halves of the sea in pursuit after Israel. Had they seen the sea open without some form of natural explanation, Egypt would not have ventured into the sea; because if it could be split miraculously, it could also come together miraculously to drown them.
2) Hashem utilizes His laws of nature as much as possible, for they were created by Him. Even though the wind would actually be ineffective, yet the impression would be gained that the wind participated in splitting the sea. Even this, although not actually effective, was the miraculous result of the foregoing action: "And Moshe stretched out his arm..."
(Similar examples of combination of natural causes together with miracles are found frequently. Hashem commanded Moshe to go up to the mountaintop to see the land of Canaan, and Moshe saw the entire land from the north to the south. This was purely a miracle, because even from the mountaintop no man can see so far. But the viewing from the mountaintop, although entirely ineffective, combined a seemingly-natural cause together with the miracle.)
There were other great disturbances of nature at this time or not long afterward. "When Israel came forth from Egypt, the house of Jacob from a people of strange language... The sea saw and fled, the Jordan turned backward. The mountains leaped like rams, the hills like young sheep" (Tehillim 114:1-4).
All of Nature was in turmoil, for a reason. "What ails you, O Sea, that you flee? O Jordan, that you turn backward? You mountains, that you leap like rams; you hills, like young sheep?" (Tehillim 114:5-6). But there was a great Reason for these phenomena: “Tremble, O earth, at the presence of Hashem; at the presence of the G-d of Jacob" (ibid. 114:7).
It was because the presence of Hashem went forth together with His beloved people, to make known that His presence rests upon the children of the Fathers; and therefore all of Nature erupted into violent action to demonstrate the approach of the Creator. These verses in Tehillim declare that mountains sank, and other mountains were created by violent disturbances of the earth’s crust. Sea floors became lofty hills, and mountain-tops were submerged.