It is said that Rabbi Eliezer, Rabbi Joshua, Rabbi Elazar the son of Azariah, Rabbi Akibah, and Rabbi Tarfon sat all night in the town of B'ney B'rak telling the story of the departure from Egypt. The talked throughout the night, until their students came to them and said, "Rabbis, it is time for the morning Shema!"

Rabbi Elazar said: I seem to be a man of seventy years, yet I did not understand why the story of the departure from Egypt should be told at night, until Ben Zoma explained it by quoting this verse: "You should rememebr the day of your going our from Egypt all the days of your life." It is easy to remember your libertion when the sun is shining. But you must remember it ALL the days of your life -- even when the sun has set, even when your day is dark. 

B'ney B'rak is a town localed outside Tel Aviv. The five Rabbis in this story were a group of teachers who lived under Roman rule during the second century, after the destruction of the Temple. Since the Temple no longer served as the focal point of Jewish life, the rabbis reconstructed Judaism with Torah study at its center.  Their telling of the Passover story was an act of great courage, as at the time the study and practice of Judaism was prohobited by the Romans, and was punshable by death.