Our Sages (Tosefta Pesachim, Chapter 3) taught: “We inquire about and expound the laws of Pesach from thirty days before Pesach.” Based on this, great rabbis throughout the generations have taken the opportunity to teach the laws of Pesach to the public between Purim and Pesach since everyone must be proficient in the laws of koshering vessels, food products, the Seder night, and more.
However, this year, 5781, there is something special we will have to discuss, which are the laws of when the Seder night coincides with Motza’ei Shabbat. We will have to explain the procedure regarding burning Chametz, for we will not be able to do so as usual since Erev Pesach falls out on Shabbat. We will also have to discuss what we are supposed to be eating on Shabbat of Erev Pesach since the prohibition to consume Chametz will already be in effect from Shabbat morning and eating Matzah on Erev Pesach is forbidden. Let us now begin studying the laws of Pesach.
The Prohibition to Eat and Benefit from Chametz
The Torah (Shemot 13) states regarding the holiday of Pesach: “Matzot shall be eaten for seven days; neither leaven nor sourdough shall be seen in your borders.”
Our Sages taught in Masechet Pesachim (21b among other places) through expounding certain verses that not only is Chametz prohibited for consumption on Pesach, it is also forbidden to benefit from Chametz on Pesach, meaning that even if one does not actually eat Chametz on Pesach, he still may not sell it to a non-Jew and the like on Pesach for this would mean that he is benefitting from this sale. Consumption of Chametz on Pesach is punishable by Karet (severance of one’s soul from the Jewish nation).
Chametz on Pesach Cannot Even be Nullified by a Ratio of One to One-Thousand
The prohibition of Chametz on Pesach is so severe that if Chametz gets mixed into other foods, it cannot be nullified even by a ratio of one to one thousand, which is not the case regarding other prohibitions.
For instance, regarding the prohibition of consuming blood, if one gram of blood falls into a pot of food, if there are sixty grams of food present against the one gram of blood that fell into it, the blood is considered nullified and this food is permitted for consumption. Regarding Chametz on Pesach, however, even if the food present is one thousand times the amount of the Chametz that fell into it, for instance if a tiny crumb of Chametz falls into a large pot of food, the entire pot of food becomes prohibited for consumption because of the crumb of Chametz that became mixed into it.
Therefore, one must be extremely careful regarding Chametz on Pesach to buy only food products that one is completely certain do not contain Chametz mixtures and are certified by a reliable Kashrut organization. Similarly, one should not rely on a non-Torah-observant Jew when he tells him that a certain food does not contain any Chametz, for instance if he says that a certain spice does not have any Chametz mixed into it, for it has already occurred that some people have transgressed the prohibition of Chametz because they had relied on a grocer with no believability. Maran Harav Ovadia Yosef Shlit”a writes that it is proper for one not to purchase any food product designated for Pesach use without a reliable Kosher for Passover certification on every single item. The same applies even to things that do not seem problematic such as liquor, Arack, and the like. Nowadays, even products that look “innocent” pose major Kashrut problems during the rest of the year and especially during Pesach, as all products contain a multitude of ingredients, as we all know.
Dishes Which Have Absorbed Chametz
One may not use the same dishes that he uses during the rest of the year on Pesach, for these dishes have Chametz absorbed in them since when a hot food is inside these dishes, the walls of these dishes absorb its Chametz flavor, just as they absorb dairy or meat flavor. Thus, one must either use dishes that are specially designated for Pesach that have not been used for Chametz or kosher (make kosher for Pesach) his Chametz dishes. This will be better explained in following Halachot.