Parshas Tzav -A day of blessings

On the eve of passover we had the opportunity to engage in a string of mitzvos that I believe was unprecedented in history. On the morning of Shabbos Hagadol I used the derasha to review these mitzvos and their blessings.
1. It began on Tuesday night with the one night a year search for chometz. Artscroll siddur pg.654
2. Wednesday morning we participated in a siyum or completion of a tractate celebration. Although a siyum may be celebrated anytime this is done annually on the eve of passover so that the first born in our midst may partake of the feast. If they didn't they would have to fast in commemoration of their salvation when Hashem slayed the firstborn of the Egyptians but passed over the houses of the children of Israel.
3. We then crossed the street to ball field three at the JCC to recite a blessing that presents itself only once every 28 years. The blessing of the sun and the earth being in the same relationship as they were on the fourth day of creation when the sun and planets were created. See Artscroll siddur pg. 228
4. Next was the annual burning of the chometz and the declaration of nullification of chometz. The Torah tells us to remove the chometz from our possesion which we fulfill by burning it. Then we ensure that we don't own any chometz by nullifying any chometz that we know of or don't know of. See Artscroll siddur pg. 654
5. In the afternoon the eruv tavshillin was placed. Although we are allowed to cook on the holiday we may only cook for the holiday but not for any other day even shabbos. How then are we to have fresh food for shabbos when the holiday occurs on Friday? It truth most of the problem is solved because we can cook on Friday for Friday and since if guests were to come unexpectedly we would serve them the food we just cooked on Friday we can cook and use that food for shabbos. So when every few years Yom Tov falls on friday our sages had us begin the cooking for shabbos on Wednesday the eve of the holiday this year. In that way when cooking on friday we would merely be adding to that which we had begun on Wednesday thereby not degrading the holiday that much. This beginning of the cooking of the meal is called an eruv (mixing ) tavshilllin (of cooked foods). We customarily take an egg and a matzoh and pronounce the blessing over the fulfillment of this rabbinical enactment. See Artscroll Siddur Pg. 654
6. Of course then it is on to seder preparations and the seder night full of once a year mitzvos.