The Talmud refers frequently to the five laws of shehitah: shehiyah (pausing), derasah (applying pressure), haladah (passing the knife under skin), hagramah (cutting at a slant), and iqur (tearing). These defects are called “hilkhot shehitah,” because they were transmitted as halakhot le-moshe mi-sinai, as the Gemara explains at the beginning of “Ha-Shohet” However, Rashi notes that not all five were transmitted as halakhot le-moshe mi-sinai, some having been inferred from the Scripture, e.g., derasah which is excluded by “ושחט”, implying that cutting must be back and forth with no downward pressure, and iqur, which is also excluded by “ושחט”. But if at least two of the five laws of shehitah can be inferred from Scripture, why are all five defects considered laws transmitted orally to Moshe, implying that none of the five can be inferred from the Scripture? Indeed, whether a halakhah is implied by Scripture or derived from an oral tradition has halakhic consequences, lashes being administered only for violations of prohibitions explicitly stated in or deduced from the Biblical text.

Moreover, the other three defects in shehitah are also implied by the Biblical text, without the aid of any oral tradition. As the Ramban explains in his commentary on the Torah, “ושחט“ means cutting the simanim — the gullet and the trachea — of the throat, that requirement being inferred from the ritual of meliqah which must be performed ”ממול ערפו” at the back of the neck, directly opposite the location of shehitah. Thus, hagramah is defective, because cutting at a slant would lead to cutting outside the required location for a valid shehitah. Shehiah and haladah are also implied by “ושחט,“ inasmuch as passing the knife under the skin contradicts the requirement that the simanim be visibly cut as required by the verse (Jeremiah 9:7) “their tongue is a sharpened arrow“ (חץ שחוט לשונם), implying that, like the cut made by an arrow, shehitah must make a visible cut; if the knife passes under the skin, the cut is not visible. Moreover, passing the knife under skin inevitably causes either downward pressure to be applied or the simanim to be torn, which is what is suggested by the only Mishnaic reference to haladah (Hullin 32b) “או שהחליד הסכין תחת השני ופסקו” as an alternative to “פסק את הגרגרת.” Since “פסק את הגרגרת ” is understood as tearing, passing the knife under the skin is presumed to cause a defective shehitah, not because it is defective in and of itself, but because it inevitably causes either tearing or the application of downward pressure. Pausing may similarly be inferred as a defect implied by the analogy between shehitah and heitz; just as an arrow cuts without pausing, so must a knife cut without pause. So any halakhah le-moshe mi-sinai concerning shehiah would specify a minimum pause required to invalidate the shehitah.

Nor would it be appropriate to infer from the analogy between shehitah and heitz that, like an arrow, shehitah requires cutting in a single direction rather than the back-and-forth motion of a knife. That inference would be unwarranted, because the Sages made only inferences from Scripture if the inferences are coherent and appropriate. The Sages understood that the essential aspect of shehitah is to cut the simanim of the neck by way of a slicing motion with no downward pressure and no tearing, so that the animal’s death is not delayed by any pause in cutting. So, if no halakhah le-moshe mi-sinai was needed to infer that cutting at a slant, passing the knife under the skin, or pausing would invalidate a shehitah, why did the Gemara assert that it is only through an oral tradition from Sinai that these defects are known?

However, Rashi at Hullin 9a (ד”ה כולהו תנינהו במתניתין) reverses his position, citing the Mishnah at Hullin 30a that if, in performing shehitah, one cuts off the head of an animal with no back-and-forth motion, the shehitah is invalid. But what the Mishnah actually says is that, without a back-and-forth motion, the shehitah would be valid if the knife is longer than the width of the animal’s neck. Rashi inferred that cutting off the animal’s head in one motion with a short knife would be invalid, because, the animal’s head could not be cut off in one motion without applying downward pressure.  But rather than cite an indirect source, why didn’t Rashi cite the explicit statement in the Mishnah that cutting off an animal’s head in one motion invalidates a shehitah? Moreover, concerning iqur, Rashi quotes the Mishnah at Hullin 32a that performing shehitah on the trachea and severing the gullet (understood by Rashi to mean tearing the gullet) renders the flesh of the animal halakhically unfit. But why didn’t Rashi cite the Mishnah at Hullin 15b explicitly prohibiting the use of a saw in performing shehitah, because the jagged edge of a saw tears, rather than cuts, the simanim?

The reason that Rashi did not cite the obvious cases of derasah and iqur mentioned in the Mishnah rather than the indirect cases is that in the obvious cases the simanim were completely severed either by applying downward pressure or by tearing, so that the shehitah would be invalid even if there were no halakhah le-moshe mi-sinai. It is only when most of the shehitah is performed properly, and just a small part performed defectively through a brief application of pressure or a slight tearing of the simanim, that a halakhah le-moshe mi-sinai was needed to teach us that the shehitah is invalidated. With no halakhah le-moshe mi-sinai, we would have assumed that improperly severing a minority of the simanim does not invalidate the shehitah as if it were nehirah. That is why Rashi cites the second statement of the Mishnah at Hullin 30b that the shehitah was performed, without pressure, in a single motion, the insufficient length of the knife requiring the application of pressure at the end of the shehitah to detach the animal’s head. Nor could Rashi have cited the Mishnah teaching us that a shehitah performed with a saw is invalid, because the entire shehitah would then have been performed improperly in contrast to the case of the Mishnah at Hullin 32b in which one siman was cut properly, and only the second was torn. So Rashi was correct to say that all hilkhot shehitah were derived from an oral tradition, because we could not have inferred from the Biblical text that even a small defect renders a shehitah invalid.

But then the question arises that lashes cannot be administered for violations not derived directly from a Biblical text. Since the Biblical text could be interpreted to require only that most of the simanim be cut without any of the five defects of shehitah, why would lashes be administered for consuming the flesh of an animal if only a small fraction of a siman was defectively cut? In his introduction to the laws of shehitah, the Pri Megaddim questions why the defective forms of shehitah other than derasah have the status of Biblical enactments, so that if it is doubtful whether a shehiitah was performed with none of the other four defects, the doubt is resolved stringently, not leniently, as in all doubtful cases concerning a Biblical prohibition. And he rules that all five defects are considered to be of Biblical origin because the Biblical text could not be understood without the halakhah that a defect in cutting part of any siman renders the animal a neveilah. This is problematic for two reasons. First, even the defect of derasah could be interpreted to apply only when all or most of the siman was cut with the application of downward pressure, so that the halakhah is supplementing what we would otherwise have inferred from the Biblical text, because it clearly would have been possible to interpret the verse “ושחט“ to require only that the most, but not all, of the siman be cut with no downward pressure. So it cannot be that the halakhah was necessary to interpret the Scripture.

Moreover, the Pri Megadim concludes by saying eating the flesh of an animal upon which shehitah was performed defectively is punishable under the Biblical law by lashes, because Moshe was taught that the verse “לא תאכל כל נבלה” classifies any defective shehitah under the categoy of neveilah. But that verse, written in parshat Re’eh in Deuteronomy after nehirah — previously valid in the desert — was invalidated, must have been intended to teach that performing nehirah would thereafter be considered neveilah. But the invalidation of nehirah does not imply that defectively cutting only a small fraction of a siman is sufficient to render the animal a neveilah.

A further difficulty with the opinion of the Pri Megaddim that the five defects that invalidate shehitah were orally communicated to Moshe at Sinai to clarify how to interpret the Scripture is that this opinion accords with neither R. Yishmael nor R. Akiva. According to R. Yishmael the verse “וזבחת” did not introduce a positive commandment to perform shehitah, the positive commandment to perform shehitah “ושחט את בן הבקר” was limited to qodshim, from which we infer that shehitah alone, by eliminating the prohibition of eiver min ha-hai, can render hullin fit to be consumed. The verse “וזבחת . . . כאשר צויתיך”, transmitted upon entry into the Land, must therefore refer to the earlier commandment to perform shehitah on qodshim, because, according to R. Yishmael, there was no halakhah le-moshe mi-sinai communicated in reference to the verse “ושחט” just as no halakhah le-moshe mi-sinai was communicated in connection with the verse “וזבחת כאשר צויתיך”. According to R. Yishmael, all the laws of shehitah, e.g., the requirement to cut both simanim of a four-legged animal and one siman of a fowl, must have been hermeneutically derived from the Scripture. The five defects invalidating shehitah, lacking any Scriptural basis, would therefore not require that lashes be administered, nor, certainly, would an animal slaughtered defectively have the status of neveilah, the Biblical prohibition of neveilah devolving upon animals slaughtered by the method of nehirah or by other invalid methods of tearing or puncturing the simanim, but not upon an animal slaughtered by a shehitah that was defective only because of a slight mistake in cutting a siman.

Nor can the position of the Pri Megaddim be reconciled with the opinion of R. Akiva that the verse “וזבחת כאשר צויתיך” teaches us, as Rebi said, that the laws of shehitah were orally transmitted to Moshe. If all the laws of shehitah were orally transmitted at Sinai, why would Rebi have stated that “כאשר צויתיך” refers to the requirement to cut the gullet and the trachea and to the requirement that a majority of both simanim be cut in a four-legged animal and a majority of one siman in a fowl, without mentioning the five defective forms of shehitah? Both Rashi and the Rambam assert that the verse “וזבחת כאשר צויתיך” implies that all the laws of shehitah were transmitted orally to Moshe at Sinai. But should not Rebi have also acknowledged that the requirement to cut a majority of both simanim in a four-legged animal and a majority of at least one siman in a fowl applied not only to shehitah, but also to nehirah, as both Rashi and the Tosafists state a number of times in their commentaries?

But it was established in Iqar 2 that, according to R. Akiva, when the Israelites were in the desert they were required to cut or sever only one of the two simanim when performing either shehitah or nehirah on four-legged animals or fowl, because both shehitah and nehirah removed the prohibition of eiver min ha-hai only within 24 hours after slaughter upon death of the animal. It was only after nehirah was invalidated upon their entry into the Land when the Israelites were commanded to perform shehitah rather than nehirah to remove the prohibition of eiver min ha-hai from hullin as well as from qodshim, that it became permissible to consume flesh taken from a live animal upon which shehitah had been performed while the animal was still in its death throes, a leniency that had not been in effect in the desert. It was because this leniency became effective simultaneously with the commandment to perform shehitah on hullin that minimum requirements for a valid shehitah were specified to ensure that the slaughtered animal would die shortly after shehitah was performed, inasmuch as shehitah would thereafter become effective immediately rather than after death of the animal.

If the halakhot prescribing minimum requirements for a valid shehitah were orally transmitted only upon entry into the Land when the commandment to perform shehitah on hullin was given, then there are two possibilities concerning the transmission of the halakhah concerning the five defects in shehitah. One is that the halakhah concerning the five defects in shehitah might also have been transmitted along with the minimum requirements for a valid shehitah, in which case a shehitah performed on qodshim in the desert would not have been invalidated if a minority of a siman had been cut defectively; the other possibility is that the defects in shehitah had already been known in the desert and had invalidated a shehitah performed on qodshim. But if the halakhah concerning the five defects was transmitted only upon entry into the Land, what source — apart from Rebi who did not mention the five defects — teaches us that the five defects would, after entry into the Land, render a shehitah on hullin or qodshim invalid? Alternatively, if it was known in the desert that the five defects invalidated a shehitah performed on qodshim, then transmitting them again upon entry into the Land would have been unnecessary, so that there was no need for Rebi to mention them in the baraita in which he deduced the oral transmission of the minimum requirements for shehitah from the verse ” וזבחת כאשר צויתיך”. The words “כאשר צויתיך” were needed, as Rebi taught, only to teach us that the minimum requirements for a valid shehitah were orally transmitted to Moshe when the Israelites, upon entry into the Land, were commanded to perform shehitah on hullin, nehirah being invalidated and shehitah becoming effective immediately rather than, as in the desert, upon death of the animal. Once shehitah became effective immediately rather than upon death of the animal, it became necessary to specify the minimum requirements for an effective shehitah, namely, properly cutting a majority of both simanim of a four-legged animal and a majority of at least one siman of a fowl. But all other laws of shehitah having remained unchanged, including the invalidation of a shehitah if even a minority of one siman is cut defectively, the five defects in shehitah must have been known in the desert to invalidate the shehitah of qodshim. But if the five defects were not known in the desert and did not invalidate a shehitah performed on qodshim, there is no source that teaches us the source that teaches us that these five defects invalidate a shehitah.

It was shown above that all five defects are hermeneutically implied by analysis of the verse ” ושחט את בן הבקר” so that no halakhah le-moshe mi-sinai was needed to invalidate a shehitah performed with any of these defects. What could not have been inferred from the text was that even if only a minority of a single siman was cut defectively, the defect invalidates the shehitah. Not only would we not have known that a defect in cutting even a minority of one siman renders the animal upon which that shehitah is performed a neveilah, we would not even have known that consuming the flesh of that animal is prohibited.

It is only through understanding a number of disputes between R. Yohanan and Reish Laqish in this tractate (especially at 29b and 32a) that we know the source of the halakhah that a defect in cutting a minority of a siman during shehitah renders the animal a neveilah. These disputes between R. Yohanan and Reish Laqish hinge on the reasoning that underlies that halakhah. The opinion of Reish Laqish is that once most of a siman is severed, the remaining unsevered portion of the siman is considered to be resting in a basket (כמנחא בדיקולא) i.e., it is disconnected from the rest of the animal, implying that the minimum requirement to perform shehitah, even ideally, is to cut a majority of the simanim, exactly the opinion of R. Oshaya in the Tosaphot discussed in the previous Iqar, that after a majority of a siman has been cut, further cutting of the siman is like cutting a limb of the animal. Thus, even the slightest defect (e.g., applying downward pressure or tearing) in cutting the first half of the siman implies that a majority of the entire siman was cut defectively, inasmuch as cutting the remainder of the siman after the first half has been cut, has no halakhic standing, so that the minimum requirements for performing the shehitah cannot be satisfied, invalidating the entire shehitah. But this reasoning implies that if a defect in the shehitah occurs, the shehitah could be restarted at another spot on its neck to prevent the animal from being rendered a neveilah, inasmuch as quickly performing a valid shehitah on the animal before its death by cutting the simanim at another spot would prevent the animal from becoming a neveilah.

According to Reish Laqish, this was R. Akiva’s position even before he retracted his opinion in response to R. Yesheivav; although R. Akiva believed that cutting one siman of an animal properly while tearing or puncturing the other does not render the animal a neveilah, he agreed that improperly cutting both simanim would render the animal a neveilah, because cutting one siman without defect suffices to avoid rendering the animal a neveilah, the proper cutting of both simanim not having been required in the desert. Nor would the animal have the status of a tereiphah because, when nehirah had been a valid method of slaughter, tearing or puncturing the first siman – an act of nehirah — did not render an animal a tereiphah. Thus, even after it was invalidated, nehirah only renders an animal a tereiphah, so that a valid shehitah performed on the animal before it succumbs to the nehirah would prevent the animal from becoming a neveilah, because it would be considered a tereiphah upon which a valid shehitah had been performed.

But in the desert performing a defective shehitah on qodshim would invalidate the animal as a sacrifice, because the verse “ושחט את בן הבקר” required a majority of at least one siman to be cut properly. However, R. Yesheivav persuaded R. Akiva to retract his opinion by invoking the tradition of R. Yehoshua that any defect in a shehitah, even if it affected only a minority of one siman, renders the animal a neveilah. Before retracting, R. Akiva believed that a defect in a minority of just one siman is not considered a defective shehitah, inasmuch as cutting both simanim was a requirement that had not existed previously and rendered the flesh of the animal unfit to be eaten but did not render the animal itself a neveilah. But R. Yehoshua maintained that, once cutting both simanim became a requirement of shehitah, any defect in cutting either siman invalidates the shehitah, and, like the formerly valid nehirah, renders the animal a neveilah. This is the understanding of Reish Laqish.

However, R. Yohanan rejects Reish Laqish’s opinion that, after a majority of a siman has been cut, the rest of the siman and whatever is connected to it is considered disconnected from the rest of the animal, as if it were lying in a basket (כמנחא בדיקולא). Consequently R. Yohanan believes that the ideal  (לכתחלה) requirement in performing shehitah is to cut both simanim completely, and, only after the fact (בדיעבד), is cutting a majority of both simanim of a four-legged animal and a majority of one siman of a fowl sufficient. These requirements are of Biblical origin based on the halakhah inferred by Rebi from the words “כאשר צויתיך”. So, if, לכתחלה, shehitah requires cutting the siman entirely, then, contrary to the position of Reish Laqish that any defect invalidates the shehitah by making it impossible to satisfy the requirement to properly cut a majority of the siman, a minimally defective cut is not disqualifying, because the proper cutting of the first part of the siman before the defective cutting occurred may be combined with the proper cutting of the last part of the siman after the defect, so that the בדיעבד requirement to properly cut a majority of the siman is satisfied. Thus, in the desert, a small defect in the shehitah would not have invalidated a sacrifice, nehirah having then been a valid method of slaughter, and even now a small defect in the shehitah does not render the animal a tereiphah; only cutting a majority of a siman defectively renders the animal a tereiphah. But after nehirah was invalidated, if one siman only is cut, with the second punctured through nehirah, or even if, after one siman is cut, the animal is left to die without the second siman being cut, the animal’s flesh may not be eaten because the minimum requirements of shehitah were not satisfied. But the animal would not thereby contract the ritual impurity of a neveilah. Thus, before withdrawing his opinion, R. Akiva believed that improperly severing most of one siman would render the animal a tereiphah, but a defect only in part of one or both simanim would not cause the animal to be prohibited, because the prohibition of nehirah through the verse “לא תאכל כל נבלה” implied only the invalidity of complete slaughter by the method of nehirah, i.e., severing most of one siman by the method of nehirah. However, R. Akiva believed that severing only a small part of a siman would not render the animal a neveilah, inasmuch any shehitah that would have been valid for qodshim in the desert cannot, if performed on hullin after entry into the Land, render the animal a neveilah. So any defect in cutting a minority of one siman could not render the flesh of the animal Biblically prohibited to be eaten, only rabbinically prohbited. But R. Yesheivav, citing the principle of R. Yehoshua that any defective shehitah has the status of neveilah, persuaded R. Akiva to retract his opinion, because, according to R. Yehoshua, a defective shehitah had been invalid even in the desert, rendering the animal unfit to be offered as a sacrifice, not because the animal had been rendered a tereiphah, but because the act of nehirah, i.e., a tearing or puncturing of a siman, even if only a minority of a siman, cannot be considered to be a valid shehitah. This principle of R. Yehoshua is not based on the verse “וזבחת כאשר צויתיך”, but from the earlier verse (Leviticus 1:5) “ושחת את בן הבקר”, implying that even in the desert nehirah was disqualifying for qodshim based on the hermeneutic interpretation of the Oral Law. Accordingly, upon entry into the Land, when the commandment to perform shehitah was extended from qodshim to hullin, nehirah became a disqualification for hullin just as, in the desert, it had been for qodshim. Therefore, once it became obligatory to cut both simanim, a defect in even one siman invalidates the entire shehitah.

Only the Rambam grasped this distinction in ruling that a puncture of the gullet (נקובת הוושט) renders an animal a neveilah even while it is alive. And his reasoning is that puncturing the gullet is an act of nehirah, so that once it is punctured, a valid shehitah cannot be performed on the animal. The same applies to the windpipe, because, after the windpipe is punctured, it would be possible to cut the windpipe in a different place, inasmuch as we do not follow the opinion that cutting the windpipe causes the windpipe and the lungs to be disconnected form the animal (כמן דמנחא בדיקולא). In interpreting the verse (כאשר צויתיך) that Moshe was commanded about the laws of shehitah, Rebi therefore could enumerate only the new laws concerning the slaughter of hullin that were transmitted upon entry into the Land, namely the ideal requirement to cut both simanim completely and that, בדיעבד, cutting a majority of the two simanim suffices for a four-legged animal and a majority of one siman for a fowl, requirements that had not previously existed for the slaughter of qodshim. Because the defective forms of shehitah had already been disqualifying in the desert for qodshim, Rebi omitted them when enumerating the new requirements for the slaughter of hullin.

However, according to R. Yishmael, there was no positive commandment to perform shehitah, a method of slaughter other than shehitah for removing the prohibition of ever min ha-hai never having existed. Thus, shehitah had always been effective only upon the death of the slaughtered animal after a majority of both its simanim had been cut, no distinction between the לכתחלה and the בדיעבד requirement for a valid shehitah having previously existed. Thus, any defect in performing shehitah would have been disqualifying under the same reasoning as that of Reish Laqish discussed above.