One of the elements that makes the prohibition of Hamets so unique is that, unlike any other forbidden foods, it includes the ban of its possession. There are three Mitsvot in the Tora related to this prohibition:
1. בל יראה “Your Hamets shall not be seen in your property” (Ex. 13:7);
2. בל ימצא. “Your Hamets shall not be found in your premises” (Ex. 12:19).
3. השבתת חמץ “You shall end [ownership of] your Hamets Pesah eve” (Ex. 12:15).
The Tora sheBe’al pe, the authoritative (halakhic) Jewish tradition, explains that the first two verses, the two prohibitions, are considered one single restriction, that is: “owning” Hamets during Pesah (emphasis on “your”, “you”,). It is forbidden to “own” Hamets, even when that Hamets is not physically IN your house. Maimonides explains this concept: In halakha 4:2 saying: ” ….Hamets [food] belonging to a Jew …, even though it is buried, or located in another city, or is entrusted to a gentile, causes him to violate [the commandments]: “[hamets] shall not be seen” and “[hamets] shall not be found.”
We also have a third Mitsva called “tashbitu” which is explained by the Tora shebe’al pe as: you shall end “the possession” of your Hamets before Pesah begins.
In sum, there are two identical prohibitions (a unique case in the Tora) and one positive commandment, virtually for the same matter: the prohibition of owning Hamets during Pesah.
Strictly speaking, (and following Maimonides opinion) these three mitsvot could be fulfilled at once just by performing one single act: the ‘bitul Hamets’, that is, renouncing wholeheartedly to the ownership of any Hamets that belongs to me, regardless of where that Hamets is located.
By declaring the Hamets ownerless, a person 1. Fulfills the Mitsva of “ending the possession of his or her Hamets” and, 2. Avoids the two prohibitions of the Tora, even though there might still be Hamets found within his premises.
But this is not what we presently do for Pesah… Why? The Rabbis explained that there might be some practical complications with just “declaring” our Hamets ownerless, while keeping it at home, and that is why they instructed us to physically “remove” all Hamets food from our houses.
What are those potential complications? First, we might declare that we do not own our Hamets anymore, but, if we posses something valuable, a bottle of an expensive whiskey for example, will we really mean wholeheartedly that we renounce to the possession of that Hamets? Second, they said, Hamets is the most common food (think about bread, crackers, pasta, cereals, etc.), so even if we declare our Hamets ownerless, while we keep the Hamets at home, we might end up eating Hamets accidentally…
This is why our Rabbis in the Mishna instructed us to actually remove (“be’ur hamets”, commonly translated as “elimination of Hamets”) all our Hamets before Pesah begins, and to renounce to the ownership of any Hamets we might still have, and have not found (“bitul Hamets”).
Following thier instructions, this is what we actually do:
(1) We clean our home, cars, offices and any other properties before Pesah begins to identify and remove all Hamets from them.
(2) We run a final search of all our properties to make sure that we have removed everything Hamets from them (Bediqat Hamets).
(3) We physically dispose of or get rid of any Hamets found in our properties before and during the search (Be-ur Hamets). We can give our Hamets as a gift to a non-Jew, or if we have bread leftovers, for example, we can throw it to the birds or to sea to fish the fish, or burn it or dispose of it in a garbage outside our premises.
(4) Then, after we get rid of our Hamets, we declare (this is the Bitul hamets): “kal hamira…” whatever Hamets we may still own anywhere, which was not detected during the bediqa and/or was not removed by us, does not belong to us anymore, and from now on it is considered ownerless (hefqer) as the dust of the earth.
In this way, we fulfill all the Biblical and rabbinical requirements: 1. Searching and getting rid of all Hames from our properties. 2. Renouncing to the ownership of any unidentified and unfound Hamets that we might still have in our premises.