Lichatchila & Bidieved

Rabbi Israel Chait




With the proliferation of Talmudic and Halachik material in English, many people feel they can learn and understand these sources without a Rebbe.


However, there are basic principles of Talmudic reasoning which must be understood clearly otherwise they will remain a source of confusion and frustration in the mind of the student. As the Rav used to say, תורה שבעל פה is a way of thinking. One of the mechanisms that reflects the method of תורה שבעל פה is the institution of לכתחלה  and בדיעבד, a preferable way of doing something and a minimal way of doing it. For instance, we say that לכתחלה one should pray at sunrise, but בדיעבד it is alright if one prays during the first third of the day. This seems strange, shouldn’t there be one correct way of doing the mitzvah of Tefilla? If sunrise is the criterion, it should not be good before or after sunrise. Why do we have לכתחלה and בדיעבד?


לכתחלה and בדיעבד , rather than being intrinsic concepts, emerge from several factors. The most primary usage of לכתחלה and בדיעבד is found in קדשים. For example, לכתחלה the אימורים (those parts of the animal that are designated for consumption on the מזבח) must be burnt on מזבח, but בדיעבד if you just did the זריקה it is good. Another example is in the condition of the Korban (sacrifice) itself. An animal with a blemish is unfit for a Korban, while a sickly-looking animal, although it may not be brought לכתחלה as a sacrifice, if it is brought, בדיעבד the Korban is valid. As Maimonides states, “Not everything that is not disqualified can we bring as a sacrifice לכתחלה” (איסורו המזבח ז“א). The reason is that in קדשים—the area of halacha that deals with sacrifices—we have two systems: one that delineates what is necessary for the institution of Korban, and another system of things that partake of servitude that are למצוה, that enhance the kohen’s מעשה עבודה (performance of worship) but are not indispensable. If they are absent, they do not affect the basic validity of the Korban. How do we know which are indispensable? The Talmud says, “שנה עליה הכתוב לעכב”, “when the Torah repeats a certain law, it is an indication that that law is indispensable.” Failing to burn the אימורים or bringing a sickly-looking animal lack in the institution of servitude of the kohen, but does not disqualify the offering. The basic institution remains intact; the one of servitude is lacking. Thus, in קדשים we have לכתחלה and בדיעבד emerging from two spheres: one of הכשר קרבן, the basic requirements to validate the Korban, and the second, the superadded requirements of servitude that are dispensable.


Another case is placing the sacrifice on the altar for consumption.  The halacha states it must be raw when it is placed on the altar. If it is broiled, it lacks in “ריח ניחח”, “pleasantness of the sacrifice” before God. However, it is still a valid sacrifice. The basic structure of the sacrifice has not been undermined. You might say descriptively, לכתחלה, you shouldn’t do it, but בדיעבד it is good.


But לכתחלה and בדיעבד is not found only in קדשים, it is also found in אורח חיים. For an example let us take לולב. We say לכתחלה we should take the four species together and shake them, but בדיעבד if you simply pick them up separately you fulfill the mitzvah. How do we explain this, unlike קדשים there are no two systems? Here, we have a concept of mitzvah בשלמותה, a mitzvah in its optimal form. The mitzvah has components. If one picks up the lulav without shaking it he fulfills the mitzvah of taking the four species, but he is lacking in the full mitzvah which includes combining and shaking them in an act of praising God based on the verse “אז ירננו עצי היער”, “All the trees of the forest will praise God.” (דברי הימים א טז:לג)


Getting back to our opening case of tefilla, here again there are two concepts: one is the time of the tefilla which is one third of the day, and two, is the unique moment when the first rays of the sun permeate the atmosphere. This is a special moment in which to praise God for being our benefactor, המאיר לארץ ולדרים עליה ברחמים“”, “Who brings light to the Earth and to those who dwell upon it, with compassion.” This brings us to the concept of “מעשה בראשית”, “creation”, and enhances the injunction of דע לפני מי אתה עומד״”, “Know before whom you stand,” which is an essential component of tefilla. Thus, here too, as in Lulav, we have the basic component of the mitzvah and the enhancement of sunrise. 


There is yet another case of לכתחלה and בדיעבד and that is when we have a מחלקת and there is a more stringent side and an easier side. We say that in certain circumstances you have a permit to follow the easier side. Inיורה דעה we have the idea of הפסד מרובה, that when there is a great loss of money to follow the stringent side, we have a “permit” to follow the easy side. So that we may say לכתחלה you have to follow the stringent side but בדיעבד you can follow the lenient side. We also have the case of where it is a great inconvenience for the ציבור (congregation) to follow the stringent side. There again we say we can follow the lenient side, e.g. like a Shabbos Goy. (The use of a Shabbos goy relies on a minority opinion.) Thus, we have three categories of לכתחלה and בדיעבד based on three different halachic structures.




The difference between אורח חיים and קדשים can be seen more clearly with an understanding of the process ofחילול , desanctification. It is the uprooting of קדושה. קדושה should not be translated as holiness. Holiness is a religious notion; קדושה is a halachic concept. It is viewed as a substance. When it is fully intact, it has a specific format and objective. There is no equivalent term in the English language for קדושה. The only way that the mind can grasp it is by studying it. In a mitzvah there is no substance. The Rambam writes in הל׳ שחיטה יד:טז that the violation of degrading an object of mitzvah is not the degradation of the object, but of the One who commanded it; חילול is not possible. The inappropriate action of the degrader of a mitzvah does not affect it; it does not change it one iota. 

Since mitzvah does not have kedusha, there is nothing to desanctify and nothing to uproot. (אע  כב שבת)   

We can see why the לכתחלה and בדיעבד of הקדש and the לכתחלה and בדיעבד of mitzvah are incommensurable. They exist in different orbits.