Almost every Yom Tov has a special Mitzvah or Mitzvot associated with it. On Rosh HaShanah, we blow the Shofar, and we make a Berachah on this Mitzvah. On Sukkot, we eat in the Sukkah and shake the Arba Minim, and both Mitzvot require a Berachah. On Pesach, one of the main Mitzvot of the Seder night is to talk about Yetziat Mitzraim, to recount how Hashem took us out of Egypt with “an outstretched arm” and many miracles. However, there is no Berachah upon performing this Mitzvah. Why not?
The Avudraham, quoting the Rif, answers that “Zeicher LeYetziat Mitzraim” “A remembrance of the exodus from Egypt” that we say during Kiddush counts as the Berachah on the Mitzvah of Sipur Yetziat Mitzraim. The Avudraham, quoting the Rashba, adds that the Mitzvah of Sipur Yitziat Mitzraim actually can be preformed by saying only one word. Therefore, if we were to say a Berachah, it would itself count as the Mitzvah. If the Berachah counted as the Mitzvah, people might not go into detail and discuss the actual the exodus from Egypt, something Chazal wanted us to discuss. Hence, they did not establish a Berachah on the Mitzvah.
The Orchot Chaim (54) suggests that the Berachot on the Matzah and Maror count as the Berachah for the Mitzvah of telling the story of the exodus. We know that according to some authorities, if a person does not have Matzah or Maror for whatever reason, he is exempt from telling the story (on a biblical level). Ergo, in order to tell the story of the exodus, we need the Matzah and Maror. Thus, the Berachot on Matzah and Maror can count for the resultant Mitzvah of Sipur Yetziat Mitzraim.
Rav Shlomo Klunger adopts a different approach. He asserts that the only Mitzvah of Sipur Yetziat Metzraim is to tell the story. In our Seder, we begin Maggid by saying how our forefathers were idol worshippers and how they went down to Egypt. This is not part of the story, so it does not require a Berachah.
Finally, the Sefat Emet offers a beautiful answer. Throughout the Torah, we have many Mitzvot. Some are logical Mitzvot, while others are difficult to understand. The Mitzvot of Shofar, Sukkah, and the Arba Minim are not logical Mitzvot. We do not know “why” these Mitzvot have to be done. However, Mitzvot such as Tzedakah, honoring one’s parents, and the Mitzvah of Sipur Yetziat Mitzraim are all logical Mitzvot. It makes sense to give charity and to honor one’s parents. These kinds of Mitzvot do not require a Berachah. So too the Mitzvah of Sipur Yetziat Mitzraim; it should be obvious that we want to thank Hashem for all of the miracles He performed for us in Egypt and for taking us out. Therefore, we do not make a Berachah on Sipur Yetziat Mitzraim. May we see similar miracles in the near future, thereby heralding the arrival of Mashiach.