The seventh day of Passover is the day the Jewish people, after leaving Egypt, crossed the Sea of Reeds, thus ending the passage from slavery to freedom.
However, the Midrashim tell us that, in reality, the people emerged from the sea on the same side from which they entered. From this we can deduce that the parting of the Red Sea did not signify a further step in the Jewish people's escape from Egypt, because if it had, they would have emerged on the other side!
As we have often explained, Hasidic philosophy draws from every event, every law of the Torah, every occurrence in life, a practical teaching for the service of God by all people, revealing the aspect of Torah of Life, that is, not just a story, but a teaching for daily life.
Moreover, Rabbi Sadia Gaon (892-942) wrote that "our people is not a people except in their Torah," meaning that the Torah makes the Jewish people, so a teaching of the Torah is nothing more and nothing less than the very essence of the Jewish people.
The parting of the Red Sea symbolizes the revelation of what is hidden. Just as the dry land, which is always submerged, was revealed when the sea parted, so too is the seventh day of Passover a day charged with the power to reveal what is hidden.
On a personal level, this means the revelation of our own essence, our neshamah—our soul—which lies hidden behind the body. This is the true meaning of freedom: when a person manages to rid themselves of everything that binds and limits them to being one way or another, different from what their essence dictates. In other words, freedom means being able to express who one truly is. That deep, inner Jewish being that we all possess, allowing it to surface and reveal itself.
On a collective level, the opening of the Sea symbolizes the revelation of God, who is hidden behind nature, but who is found in every stone, in every plant, in every animal, in every human being.
The seventh day of Passover, then, is the day that contains, with the greatest force and power, the energy of the Messiah, who will soon be revealed in our days.