Summarized by Aviad Hacohen. Translated by Zev Jacobson.
Rava states (Pesachim 40a) that it is a mitzva to pre-wash the grain that one intends to use for baking matza (letita). This is based on the pasuk (Shemot 12:17): "U-SHEMARTEM et ha-matzot - And you shall GUARD the matzot" (ensuring that they do not become chametz). Shimur, "guarding," is only relevant where there is a real danger of imminent chimutz (fermentation). Rava is also assuming that the requirement of shimur should be fulfilled even before the water is added to the dough at the time of kneading. This implies that one should take active measures to ensure that the possibility of chimutz come about earlier, and this is achieved by wetting (washing) the grain.
The gemara further raises the logical possibility that one could fulfill the obligation of shimur from the time that the matza is put in the oven to bake (she'at afiya). The conclusion reached is that since Rava does NOT suffice with shimur from the time of baking alone, it is evident that he requires shimur for the ENTIRE process of making matza - from the very first stage (reaping - ketzira) until the very end (afiya).
Rava's opinion is based on three assumptions:
1. The obligation of shimur is in effect for the ENTIRE process of making matza.
2. The beginning of the process is defined as the time of REAPING.
3. One cannot fulfill the obligation of shimur without WASHING the grain.
Although Rava's opinion is based on all three assumptions, they are NOT entirely dependent on each other. Thus, it is possible to require shimur for the ENTIRE process (assumption #1), but to define the beginning of the process as she'at LISHA (kneading) and NOT she'at ketzira (assumption #2). It is also possible to require shimur from the time of reaping (assumptions #1 and #2), yet not compel one to do letita (washing of the grain) in order to fulfill his obligation. These points will be dealt with later in the shiur after we examine the mitzva of letita and shimur in more depth.
B. Le-chatkhila or Be-di'eved
From the statement of Rava in Pesachim, "MITZVA liltot," it is not clear what the halakha is if one did NOT wash the grain. On the one hand, it is possible that although one has failed to fulfill a positive commandment, the matza that is subsequently baked is no different from matza that prepared properly (i.e. letita is necessary only le-chatkhila). On the other hand, perhaps the matza that is subsequently baked does not meet the necessary standards and may NOT be used to fulfill one's obligation on the first night of Pesach (i.e. letita is necessary even be-di'eved).
C. Cheftza or Gavra
This issue is perhaps dependent on how one views the NATURE of the mitzva of shimur. Shimur can be viewed as an obligation of the person (GAVRA): just as one is obligated to put on tefillin, so too he is obligated to perform the mitzva of shimur. In this case, matza baked from grain that was NOT washed is no different from matza that was baked according to the required standards. Thus, shimur is necessary only LE-CHATKHILA. However, shimur can alternatively be viewed as relating to the entity (CHEFTZA) of the matza itself: just as matza must be made from one of the five species of grain, so too it must be made from grain that was actively protected from the danger of becoming chametz. According to this understanding, matza that was not made in the correct manner may NOT be used for the mitzva of akhilat matza on the first night of Pesach. Thus, shimur is necessary even BE-DI'EVED.
The Ramban (on the sugya) relates to this question and reaches the conclusion that letita is required only le-chatkhila, in order to properly fulfill the injunction of "u-shemartem." According to our explanation, we can conclude that the Ramban views shimur as a mitzva on the gavra. This approach is somewhat difficult to maintain, as the mitzva of shimur is not counted as one of the 613 mitzvot. (If shimur is part of the definition of the cheftza of the matza, it would not be counted as a separate mitzva.)
D. Levels of Shemira
In order to account for this difficulty in the Ramban, we must examine the assumption that led us to conclude that if letita is required only le-chatkhila, it must be a mitzva on the gavra and not the cheftza. Our argument above was based on the logic that letita and shimur are synonymous (the only way to perform the mitzva of shimur is by washing the grain) and thus, the Ramban, who requires letita only le-chatkhila, also requires shimur only le-chatkhila. It is entirely possible, however, that although shimur is a din in the cheftza of the matza, there is more than one way of fulfilling the mitzva of shimur. Le-chatkhila, one should use grain which was washed; be-di'eved, even if one merely took care that the grain not ferment, he has discharged his obligation of shimur. Thus, even the Ramban could agree that SHIMUR is a din in the cheftza of the matza (and is required even be-di'eved), but LETITA is required only le-chatkhila so as to perform the injunction of "u-shemartem" in the best possible fashion.
The gemara concludes that, according to Rava, shimur is required from the time of REAPING (she'at ketzira). Is this only le-chatkhila or even be-di'eved?
The Ramban notes that shimur from the time of ketzira is possibly a be-di'eved requirement, and it is not the same as shimur of letita which is required only le-chatkhila to fulfill the mitzva in the best possible way. However, he raises the possibility that even be-di'eved, the basic level of shimur is only required once water is added to the flour (when kneading begins).
Thus, according to the Ramban, there are TWO possibilities as to when shimur is required even be-di'eved:
1. Mi-She'at KETZIRA - from the time of REAPING.
2. Mi-She'at LISHA - from the time of KNEADING.
We will now attempt to explain what the logic behind each of these possibilities is. [Note: Although the Ramban mentions TWO possibilities (ketzira and lisha), theoretically, many other options exist. For example, one could claim that the mitzva of shimur begins even BEFORE ketzira, when the grain is still attached to the ground. Alternatively, as suggested in the gemara, it may apply only AFTER lisha - perhaps just from the time of BAKING. We will deal with this issue in the course of the shiur.]
1. Shimur mi-She'at KETZIRA
The gemara concludes that Rava requires shimur from the time of ketzira onwards. The most straightforward explanation is that we wish to be one hundred percent certain that the grain does not ferment and are unwilling to take any chances. Thus, the chametz must be guarded from the first instant that it is exposed to the danger of chimutz until it is has been completely baked. However, this position is somewhat difficult to maintain in light of the gemara (Pesachim 33a) which raises the possibility that grain can ferment even while it is still ATTATCHED to the ground (i.e. BEFORE ketzira). If this is the case, Rava should require shimur before the grain has been reaped and not only mi-she'at ketzira. Thus, an alternative explanation for the opinion of Rava must be found.
A careful analysis of the pasuk which is the source of the law of shimur ("u-shemartem et ha-MATZOT") may provide us with a more satisfactory answer: the Torah commands one to guard the MATZOT. Quite obviously, the mitzva of shimur cannot apply once the matza has been fully processed (and has become matza - as opposed to being merely grain or dough), as it no longer can become chametz. Nonetheless, by using the term "matzot," the Torah itself provides the guideline as to when the mitzva of shimur applies: It can be argued that matza is matza only when it is considered an "okhel" (food). It therefore follows that there must be an entity of "okhel" in existence for the mitzva of shimur to apply. Grain that is connected to the ground is considered to be part of the ground and is not recognized as a separate entity of food (e.g. it cannot become tamei). Thus, although the possibility of chimutz exists, the mitzva of shimur does not apply.
2. Shimur mi-She'at LISHA
There are a number possibilities to explain the opinion that the mitzva of shimur applies only from the time of KNEADING:
I. DERIVATION from the pasuk: Previously we explained that the name "matza" applies when there is a status of "okhel." However, it is possible that the defining quality of matza is the fact that it is termed "lechem" (bread) - albeit "lechem oni" - and thus the mitzva of shimur applies only once an entity of "lechem" has been created. In this regard, the stage of LISHA is critical, as is evident from the law of "hafrashat challa" (separating a portion of the dough to be given to a kohen). Only once water has been added to the flour is the resultant mixture termed "lechem" and one is obligated to separate a portion. Similarly, the mitzva of shimur should only apply once water has been added to the flour (i.e. mi-she'at LISHA).
II. PROBABILITY of chimutz: Theoretically, chimutz can take place even while the grain is still attached to the ground or after it has been reaped. Nevertheless, the greatest probability of this occurring is once water has been added to flour. Thus, the Torah mandates that one exercise special caution only from the stage of LISHA onwards.
III. INTERNAL vs. EXTERNAL factors: Shimur is necessary only to prevent chimutz taking place as a result of the process of making matza (u-shemartem et ha-MATZOT). Before lisha, the possibility of chimutz is external. It is only once water is added to the flour (an integral part of making matza) that the obligation of shimur comes into effect to prevent chimutz from arising from the process of making matza itself.
IV. LISHA is the BEGINNING point: Although one is commanded to perform shimur for the ENTIRE process of making matza, the beginning of this process is defined as LISHA. Beforehand, one cannot be said to be involved in making matza, as the actions that he is doing are too far removed from the final product to be considered an integral part of making matza (despite the fact that they are indispensable). For example, one who ploughs his field to plant grain that will be used for matza cannot be said to be making matza at this point in time. This too, is derived from the pasuk "u-shemartem et ha-MATZOT," you shall perform shimur from the time that MATZOT are being produced.
According to the above, there two possible areas of dispute which result in the disagreement whether shimur applies mi-she'at ketzira or mi-she'at lisha:
1. what is DERIVED from the word "matzot" ("okhel" as opposed to "lekhem" or "process" of making matza);
2. what level of PROBABILITY does one have to concern himself with in order to necessitate shimur.
3. Shimur mi-she'at AFIYA
There is an opinion in the gemara that shimur is required only for the actual baking. This standpoint can be explained as follows: Based on the assumption that the mitzva of shimur is necessary to create a CHEFTZA of matza (termed matza MESHUMMERET - shmura matza), it is possible that only a symbolic action is required to define the resultant product as matza meshummeret. Accordingly, it is sufficient to perform shimur from the time of BAKING alone. Shimur is not a cautionary action whose efficacy is measured by the removal of the danger of any chimutz, but rather a positive action which grants a special status to this matza.
It could be argued, however, that once the matza is being baked, it is too late to perform a symbolic action that will define the final product as matzat mitzva. By this stage, one is no longer acting upon the mixture directly and is only a passive onlooker to the baking process. Thus, a symbolic action which could affect the status of the matza would be required BEFOREHAND while one is still actively affecting the dough, possibly mi-she'at LISHA. Alternatively, shimur could be required only during lisha and NOT at ALL afterwards.
E. Shimur as a DEFINING Characteristic of MATZAT MITZVA
Until this point, we have dealt mainly with the different time-periods from which shimur is required. Although we mentioned that shimur affects the CHEFTZA of the matza, we will now focus more directly on how shimur operates in defining the matza that one wishes to eat in order to fulfill his obligation on the first night of Pesach. This will be done by examining how matzat MITZVA differs from matza which is simply not chametz.
The gemara (Pesachim 36a) rules that one CANNOT fulfill the mitzva of akhilat matza with matza ashira (matza that was made by kneading the flour with wine, oil, or date-honey). This is because the Torah (Devarim 16:3) enjoins us to eat "lekhem oni" (poor man's bread), and matza ashira (rich matza) does not fall into this category.
The Rambam (Chametz u-Matza 6:5) rules that one CAN fulfill one's obligation with matza that has been kneaded with fruit-juice. However, one CANNOT knead with wine, oil or milk, as the Torah requires lekhem oni. It may be deduced from the Rambam that the only problem with the latter type of matza is as a result of the necessity of lekhem oni, and would this condition, theoretically, not apply - such matza could be used on the first night of Pesach.
The Ramban (Milchamot Hashem - 10b in the Rif), however, disqualifies such matza from a different angle: Matza that does not have the possibility of becoming chametz cannot be used on the first night of Pesach, because it is excluded from shimur. Since only water can cause fermentation, matza ashira is not considered matzat mitzva. Thus, in distinction to the Rambam, even matza that was kneaded with fruit-juice is no good. Furthermore, even without the condition of lekhem oni, matza kneaded with wine, oil or milk would not be fit for the mitzva of akhilat matza. Thus, the gemara uses "lekhem oni" to disqualify specifically matza that was kneaded with a mixture of BOTH water and wine (or water and oil or date-honey). Even though it has the potential to become chametz (because of the water), it cannot be used as matzat mitzva since it is matza ashira.
One could defend the position of the Rambam and argue that matza that was made without adding water still has the potential of being chametz, since the grain can come into contact with water before being ground into flour (i.e. NOT as part of the kneading process). This leads us to conclude that, according to the Ramban, the possibility of chimutz must result from an integral part of the matza-making process and that the concept of shimur is only relevant if one purposefully added water to the flour.
However, we are now faced with an internal problem in the Ramban: This explanation of the Ramban contradicts his assertion that shimur is required BEFORE she'at LISHA (i.e. mi-she'at KETZIRA). If shimur is necessary to avoid chimutz from EXTERNAL sources, then matza that has the possibility of becoming chametz through external sources should be considered matzat mitzva. (In other words: If we take external sources of chimutz into account with regard to SHIMUR, we should also take them into account with regard to defining matzat mitzva as matza that, inter alia, has had the possibility of becoming chametz.)
Thus, we must explain that there are in reality TWO TYPES of SHIMUR:
1. PASSIVE shimur which is merely PREVENTATIVE in nature. This is to ensure that none of the ingredients which are used to bake the matza become chametz. The shemira begins mi-she'at KETZIRA, even though the concern is from EXTERNAL causes of chimutz.
2. In addition there is an ACTIVE shimur which is necessary to define the matza as an entity of matza MESHUMMERET. This shimur can only take place when the process of making the matza reaches its climax when there is a danger of chimutz from internal ingredients.
Thus, according to the Ramban, the first time of shimur is required mi-she'at ketzira and the second, mi-she'at lisha.
F. Nafka Minot
There are three further possible nafka minot based on whether shimur is PASSIVE or ACTIVE:
I. Shimur by a Minor
Shimur performed by a katan (minor) is invalid. However, the Rosh (Pesachim 2:26) quotes a discussion of the Ge'onim concerning shimur performed by a minor under the SUPERVISION of an adult. According to the Beit Yosef, this issue is dependent on the question of whether a supervised minor can write a get.
According to the Rav zt"l, however, this issue is dependent on the chakira we raised previously: If shimur is merely a PASSIVE action to ensure that the matza does not become chametz, we can entrust this task to a katan if he is properly supervised by an adult. However, if it is necessary to have an ACTIVE shimur in order to create a cheftza of matzat mitzva, a katan who does not have sufficient da'at is unequal to the task, despite the fact that he is under close supervision.
II. Shimur by a Nokhri
According to the Orchot Chayim (and the Beit Yosef's understanding of the Ra'avya), the shimur of a nokhri (non-Jew) at the time of LISHA is NOT sufficient - the supervision of a Jew is required. However, even a nokhri can perform shemira at the time of BAKING. The critical moment in creating a cheftza of matzat MITZVA is she'at lisha and this cannot be achieved by a nokhri, since ACTIVE shemira is required. However, the shemira at other times is intended merely to ensure that chimutz does not take place and this PASSIVE shemira can be entrusted to a nokhri.
III. Shimur of Matzat MITZVA as opposed to REGULAR Matza
The Rambam writes (Chametz u-Matza 5:9) that by stating "u-shemartem et ha-matzot," the Torah enjoins us to take care that the grain does NOT come into contact with water mi-she'at KETZIRA, thus ensuring that we will not eat chametz on Pesach. The Maggid Mishneh notes that NO distinction is made by the Rambam between the matza of the first night of Pesach (Matzat MITZVA) and other matza - ALL require shimur.
However, further on (8:13), the Rambam distinguishes between matza that is MESHUMMERET and is fit to be eaten as matzat mitzva, and matza that is NOT meshumerret. Consequently, the Pri Chadash concludes that there are two levels of shimur:
1. Ensuring that chimutz does not occur - this applies for ALL seven days and is merely a PREVENTATIVE measure.
2. An active shimur that is necessary to create matzat mitzva.
(This shiur was originally delivered in summer 5756.
This summary was not reviewed by Harav Lichtenstein zt”l.)