וַיָּבֹ֧אוּ בְנֵֽי־יִשְׂרָאֵ֛ל בְּת֥וֹךְ הַיָּ֖ם בַּיַּבָּשָׁ֑ה וְהַמַּ֤יִם לָהֶם֙ חֹמָ֔ה מִֽימִינָ֖ם וּמִשְּׂמֹאלָֽם׃
И пошли сыны Израилевы среди моря по сухой земле; и воды были для них стеной справа и слева.
Chizkuni
ויבאו בני ישראל בתוך הים, “the Children of Israel went into the midst of the sea;” the Israelites did not cross the sea by using it as a convenient crossing on their way to the land of Canaan, as it is well known that there is no sea separating Egypt from the land of Canaan. The only reason they had to enter the sea at all, was to give G-d a chance to lure the Egyptians to their death through pursuing the Israelites. This is why they turned back from the desert of Eytam to the sea.
Kli Yakar
“And the children of Israel came into the midst of the sea on dry land.” Here it places midst of the sea before dry land but later it says the opposite: and the children of Israel walked on dry land in the midst of the sea. Also, that entire verse appears redundant. Here it says and the waters were a wall [chomah] for them spelled with a vav, but later it says “chomah” without a vav. In the Yalkut (Beshalach 238), it concludes that this is an expression of anger and fury, because Israel was subject to judgment — whether to be saved or to drown with the Egyptians.
Following this approach, we can say that there were different groups among Israel at the sea. Some were righteous, while others were of little faith, like Noah, about whom it is said because of the flood waters (Genesis 6:7) — for he did not enter the ark until the flood waters forced him to.
The good among Israel immediately entered the sea in its middle, even though they had not yet seen the dry land. Nevertheless, they believed in God and entered the midst of the sea, and afterward saw the dry land. For them, the waters were a protective wall [חומה with a vav].
But the lesser ones, untrustworthy children, first walked on the dry land because they did not believe in God. Therefore, they did not enter the midst of the sea until they first saw the dry land. For them, the waters were fierce anger [חמה without a vav], as they were subject to judgment whether to be saved or drowned.
For this reason, it says above and they came, indicating that immediately upon their arrival they entered the sea before seeing the dry land. Below it says they walked, because even though they saw the dry land, they still didn’t believe until they first walked on the dry land and only afterward entered the midst of the sea.
Following this approach, we can say that there were different groups among Israel at the sea. Some were righteous, while others were of little faith, like Noah, about whom it is said because of the flood waters (Genesis 6:7) — for he did not enter the ark until the flood waters forced him to.
The good among Israel immediately entered the sea in its middle, even though they had not yet seen the dry land. Nevertheless, they believed in God and entered the midst of the sea, and afterward saw the dry land. For them, the waters were a protective wall [חומה with a vav].
But the lesser ones, untrustworthy children, first walked on the dry land because they did not believe in God. Therefore, they did not enter the midst of the sea until they first saw the dry land. For them, the waters were fierce anger [חמה without a vav], as they were subject to judgment whether to be saved or drowned.
For this reason, it says above and they came, indicating that immediately upon their arrival they entered the sea before seeing the dry land. Below it says they walked, because even though they saw the dry land, they still didn’t believe until they first walked on the dry land and only afterward entered the midst of the sea.
Sforno
הלכו ביבשה, seeing the deep parts under the sea had all become frozen from the east wind so that the Israelites were crossing on frozen mud.