The Haggadah relates that:
In every generation a person is obligated to regard himself as if he had come out of Mitzrayim, as it is says: “You shall tell your child on that day, it is because of this that Hashem did for me when I left Mitzrayim.”
In this mp3, Rabbi Moshe Gordon explores some of the classical approaches to understanding and fulfilling this Mitzvah. You can download it here.
And here is an amazing series of Shiurim by Rabbi Gordon on the Seder and the Haggadah which covers the major Rishonim, Achronim and Poskim on the mitzvos of Pesach night and the Hagaddah.