1) WHICH SHOE TO PUT ON FIRST
QUESTION: According to Rebbi Yochanan, one should put on the left shoe first, in order to show deference to the Tefilin which are worn on the left arm. The Beraisa, on the other hand, maintains that one should put on the right shoe first. Rav Nachman bar Yitzchak concludes that a G-d-fearing person, like Mar brei d'Ravna, should satisfy both opinions by putting on the right shoe first and tying the left shoe first.
How does this satisfy both opinions? It seems to contradict both opinions, since neither the right shoe nor the left shoe is completely donned first.
ANSWER: TOSFOS (DH v'Sayem) answers that when Rebbi Yochanan says that one should put on the left shoe first because the Tefilin are placed on the left arm, he means that since the Tefilin are tied to the left arm, the left side takes precedence when it comes to tying. Therefore, by tying the left shoe first (even though one dons the right shoe first), one fulfills Rebbi Yochanan's opinion. The Beraisa maintains that the right shoe should be donned first, and it is not concerned with which shoe is tied first. According to Rav Nachman bar Yitzchak and Mar brei d'Ravna, Rebbi Yochanan does not argue with the Beraisa.
2) SUMMARY: "MUMCHEH KAMEI'A" AND "MUMCHEH GAVRA"
The Gemara discusses what makes a Kamei'a (an amulet for healing) into a Kamei'a Mumcheh (one that has been proven to be effective), which one may wear in Reshus ha'Rabim on Shabbos regardless of the level of expertise of the doctor who wrote it. The Gemara also discusses what makes a doctor into a Rofeh Mumcheh (who has been proven to be an expert healer with his amulets), such that any amulet written by him may be worn in Reshus ha'Rabim on Shabbos. In order to better understand the Gemara, it is important to review several rules:
(a) There are three factors involved with giving a doctor or a Kamei'a the status of a Mumcheh:
1. the Kamei'a that was used
2. the doctor who wrote it
3. the person who was healed by it.
The Rishonim also mention a fourth factor -- which sickness the Kamei'a was intended to cure. However, this is not really an additional factor, but it is included in the first (the Kamei'a that was used). The practice was to write a different type of Kamei'a for each type of sickness, and to write the same type of Kamei'a for the same sickness. Therefore, for which sickness the Kamei'a was written is really the same as which Kamei'a was written (#1 above).
(b) The success of the cure may depend on the Mazal of the doctor, the Mazal of the sick person, or both. However, when a Kamei'a is proven effective, its success is not attributed to its Mazal but rather to the wisdom that went into writing it. The effectiveness of the doctor, on the other hand, can depend on his Mazal (RASHI 61b, DH Mazlei, and RAN there, who writes this more clearly). Thus, a doctor who is a "Mumcheh" may have propitious Mazal, while the "Mumcheh" status of the Kamei'a is determined solely by the skill and expertise involved in writing it.
(c) A Kamei'a becomes Mumcheh by successfully curing an illness three times, even if it was written by one doctor, or if it healed the same patient three times. We do not attribute the success of a Kamei'a that worked three times to the patient's Mazal or to the doctor's Mazal. Thus, if a doctor wrote one Kamei'a three times (and it was successful every time), the doctor does not become Mumcheh. The reason for this is either because the success of the Kamei'a depends on wisdom, and not on Mazal (Rashi DH Mazlei, and RAN), or because the Kamei'a is the main factor in improving the health of the sick person, since without the Kamei'a the doctor has no chance of curing the illness (RITVA). (Rashi at the beginning of the Sugya seems to contradict this when he writes that the doctor does become Mumcheh if he wrote the successful Kamei'a three times; see Insights to Shabbos 61:4.)
3) "MUMCHEH KAMEI'A"
OPINIONS: What is a Kamei'a Mumcheh? What makes it Mumcheh?
(a) RASHI says that the Mumcheh Kamei'a refers to the charm (that is, the specific script) that is written inside the amulet. Once that charm becomes Muchzak (it has worked three times consecutively), it may be written by any doctor to cure that illness, and it may be worn outside on Shabbos. According to Rashi, in order for a doctor to become Mumcheh, he must write three different successful charms. Once he has written three different successful charms, he may now write any charm, and one may wear it outside on Shabbos.
(b) TOSFOS and ROSH (6:8) disagree and say that just because a doctor knows how to write three charms is no proof that every charm he writes from then on will be successful. They therefore say that what Rashi describes as making the Kamei'a Mumcheh is actually what makes the doctor Mumcheh. A doctor who is Mumcheh, then, is one who has written one charm successfully three times. Mumcheh Kamei'a, according to Tosfos and Rosh, means that the very same amulet (that is, the actual piece of parchment itself) worked three times. Such an amulet may be worn by anyone on Shabbos. According to Tosfos, if the same text of that amulet is re-written and another amulet is made, even though it contains the same text as the successful amulet, it is considered an entirely new and different amulet.

61b----------------------------------------61b

4) WHAT MAKES A KAMEI'A "MUMCHEH" AND A DOCTOR "MUMCHEH" ACCORDING TO RASHI
QUESTIONS: The Gemara discusses what makes a Kamei'a (an amulet for healing) into a Kamei'a Mumcheh (one that has been proven to be effective), which one may wear in Reshus ha'Rabim on Shabbos regardless of the level of expertise of the doctor who wrote it. The Gemara also discusses what makes a doctor into a Rofeh Mumcheh (who has been proven to be an expert healer with his amulets), such that any amulet written by him may be worn in Reshus ha'Rabim on Shabbos.
RASHI says that a doctor who writes the same Kamei'a three times does not become a Mumcheh to write other Kamei'as (this is Rav Papa's third case, "Chad Kamei'a l'Telasa Gavri"). Why, then, does Rashi write elsewhere (61a, DH d'Mumcheh; 61b, DH v'Ha) that the doctor who writes one Kamei'a three times is a Mumcheh?
RASHI (DH v'Itmachi) is discussing the case in which a doctor wrote nine Kamei'as, three different charms for each of three different people, and they were all successful in healing the illnesses for which they were written. Rashi asks two questions. First, why does this make the Kamei'a Mumcheh? We should say that the Kamei'a is not Mumcheh, and the success of the cure is due instead to the Mazal of the doctor! Rashi answers that a doctor does not have Mazal; he has wisdom, and it must be his wisdom which made these Kamei'as successful. Therefore, the Kamei'as themselves become Mumcheh.
Second, Rashi asks that perhaps it was the patient's Mazal that caused him to be cured, and not the doctor's expertise nor the Kamei'a's potency. Rashi answers that it cannot be the patient's Mazal, because this Kamei'a was successful in curing three different patients, and not the same person three times.
There are four points in this Rashi which need clarification:
(a) Rashi says that if we could attribute the Kamei'a's success to the Mazal of the doctor, we would not give the Kamei'a the status of Mumcheh. However, Rashi himself states (DH Mazlei) that we attribute the success of a cure to the Kamei'a and not to the doctor or patient! (His reason is because the Kamei'a is the primary curing agent, more so than the doctor or the patient. See (c) of Insight #2 above.)
(b) Rashi concludes that the doctor is not successful due to his Mazal, but because of his ability to write the Kamei'a. This contradicts what Rashi writes later (in DH Mazlei), where he says that the doctor's success could be due to his Mazal.
(c) Rashi asks that perhaps we should not attribute the successful cure to the Kamei'a, but rather to the patient's Mazal. However, later (in DH Mazlei) Rashi says that the Kamei'a overrides the patient's Mazal!
(d) Rashi answers his second question by saying that three different patients were healed (by each Kamei'a). However, Rashi himself writes (in DH Telasa Telasa) that each Kamei'a worked for only one person, and not for three people!
ANSWERS:
(a) There are two basic answers to the first question on Rashi.
1. The first answer is evident in Rashi's words elsewhere (on 61b, DH Gavra). It is true that the doctor does become Mumcheh through writing one Kamei'a three times. Rav Papa simply means that the doctor becomes an expert only for writing this Kamei'a, and not for writing other Kamei'as.
We may ask, though, why does it matter that he is Mumcheh to write this Kamei'a? Anyone can write this Kamei'a, because the Kamei'a itself has become Mumcheh! What does this doctor's expertise add to this Kamei'a if even a non-Mumcheh doctor can write this Kamei'a?
We may suggest an answer based on the words of TOSFOS (61a, DH Af Al Gav). Tosfos explains that if a Kamei'a is a Mumcheh or if a doctor is a Mumcheh, and the Kamei'a or doctor then fails to cure three consecutive times, he loses his Mumcheh status. Accordingly, we may suggest that if this Kamei'a -- which became Mumcheh by being written and used successfully three times by this doctor -- fails three times when written by other doctors, it loses its Mumcheh status and may not be carried on Shabbos if written by any other doctor. However, the doctor who is a Mumcheh to write this Kamei'a retains his Mumcheh status and he may still write this Kamei'a (to be worn outside on Shabbos). Rashi teaches that even though the Kamei'a lost its Mumcheh status with regard to other doctors, this doctor is still a Mumcheh for the writing of this Kamei'a.
2. The TOSFOS HA'ROSH suggests another answer to the first question, and his resolves the other questions on Rashi as well. Rashi (DH Mazlei) means that the success of the cure is attributed to the charm rather than to either the Mazal of the doctor or the Mazal of the patient. However, when there is a possibility that both the Mazal of the doctor and the Mazal of the patient are working together, then the possibility that the cure is a result of the combination of the two Mazalos outweighs the possibility that the cure is a result of the potency of the Kamei'a. Therefore, when one doctor used the Kamei'a three times on one patient, we do not assume that the Kamei'a is a successful one, but that the cure was a result of the doctor's and patient's combined Mazal.
This answers the first question -- why does Rashi say that perhaps it is the Mazal of the doctor that effects the cure? Rashi is referring to the case of Rav Papa, in which one doctor used the same Kamei'a to heal the same person three times. In that case, it is true that we attribute the success to the Mazal of the doctor (in combination with the Mazal of the patient).
The words of the Tosfos ha'Rosh also answer the other three questions, as follows.
(b) When Rashi answers that it is not the doctor's Mazal but his wisdom that effects the cure, Rashi is referring to the case where the doctor was successful in using nine Kamei'as to heal three people, each with three illnesses, which makes him a Mumcheh. Since he succeeded with three different Kamei'as, we no longer attribute his success to his Mazal, but rather to his wisdom. However, until he becomes a Mumcheh, we do not say that it is his wisdom that cures, but rather his Mazal, as Rashi says (in DH Mazlei).
(c) The answer to the third question is that when Rashi says that perhaps the cure is due to the patient's Mazal, he does not mean that the patient's Mazal prevents us from determining that the Kamei'a is a Mumcheh. Rather, he means that the patient's Mazal prevents us from determining that the doctor is a Mumcheh to heal other illnesses. Accordingly, Rashi's statement that perhaps we should attribute the successful cure to the patient's Mazal (as opposed to the doctor's expertise), he does not contradict his words later (in DH Mazlei) when he says that the Kamei'a overrides the patient's Mazal.
(d) This also answers the fourth question. Rashi means that three different people were healed by this doctor (and not by each Kamei'a).

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