1) AGADAH: "KOL HA'MOSIF GORE'A"
QUESTION: The Gemara cites three sources to prove that "Kol ha'Mosif Gore'a," which literally means that whoever attempts to add actually subtracts. The Gemara proves this from the verses that describe the sin of Chavah when she ate from the Etz ha'Da'as (Bereishis 3:3), the measurements of the Aron (Shemos 25:10), and the eleven curtains of goat-hair that were spread over the Mishkan (Shemos 26:7).
Why does the Torah hint to this principle specifically in these three verses?
ANSWER: The Gemara does not merely this principle from the spelling of the particular words in the verses, but from the theme that each verse represents.
The simple understanding of the Gemara's proof from the verse about Chavah is that the Gemara derives that adding is detrimental because Chavah's addition to Hash-m's command caused her to sin. On a deeper level, the Gemara is proving that anyone who tries to add to himself through arrogance actually detracts from his worth instead and makes himself less honorable. The Gemara in Megilah (29a; see also Sotah 4b) says that a Ba'al Ga'avah, an arrogant person, is considered a Ba'al Mum, a blemished person; he has made himself less respectable. This theme is learned from Chavah, who ate from the Etz ha'Da'as because of the promise of the Nachash that by doing so she would become like Hash-m. Instead of adding to her character, her action caused her to become more human and humbled, as the verse (Bereishis 3:7) implies when it says that she realized that she was unclothed and covered her nakedness after she ate from the Etz ha'Da'as. The Gemara later in Sanhedrin (38b, and Chagigah 12a) alludes to this when it says that Adam ha'Rishon was created so tall that he reached from the earth until the heavens, but after his sin, Hash-m diminished his size. His sin caused him to become smaller.
The Gemara derives from the length of the Aron that "Kol ha'Mosif Gore'a." The Torah alludes to this concept in the Aron because the Aron represents Torah and the acquisition of knowledge (see Yoma 72b). A person should always view himself lacking in Torah knowledge so that he will always strive to learn more. If he is arrogant and thinks that he knows all of the Torah already, then he will lose even what he does know. The Gemara (Eruvin 54a) teaches that one can acquire Torah only if he makes himself lowly, like the sand of a desert over which everyone else tramples. Similarly, the Gemara (Sotah 5a) says that Hash-m gave the Torah on the lowest of mountains, Har Sinai, to teach the importance of humility when learning Torah. Likewise, Torah is compared to water; just as water flows to the lowest place, so does Torah become established only in the humble person (Ta'anis 7a; see there).
The same can be learned from the dimensions of the Shulchan (Shemos 25:23). The Torah uses the same word ("Amasayim") that it uses to describe the dimensions of the Aron, from which the Gemara here learns that "Kol ha'Mosif Gore'a." (This is the only other place in the Torah where the word "Amasayim" is used. When the Torah describes the Mizbe'ach ha'Ketores, it says, "v'Amasayim," but since it has a prefix "Vav" and the "Alef" is not at the beginning of the word, one cannot learn from there that "Kol ha'Mosif Gore'a." According to the TORAS CHAIM and VILNA GA'ON (in Kol Eliyahu), the concept of "Kol ha'Mosif Gore'a" is derived from the "Vav" of "Amasayim va'Chetzi Orko." Without the "Vav" of "va'Chetzi," the verse would mean that half of its length is two Amos, and the total length is four. Again, the only other place in the Torah where the word "va'Chetzi" is used in this context is with regard to the Shulchan, where it says "Amah va'Chetzi Rochbo." The dimensions of the Mizbe'ach ha'Ketores, in contrast, have no half-measures.) The Shulchan represents the wealth and prosperity of royalty. A king, however, is commanded to be careful not to amass more money, horses, and wives than he needs, lest it lead him to arrogance and sin (Devarim 17:16-17, 20). If he thinks that he can amass more (and be "Mosif") without sinning, he will fail and ultimately fall to sin, as the verse relates about Shlomo ha'Melech.
Finally, the Gemara proves that "Kol ha'Mosif Gore'a" from the verse that describes the eleven curtains of goat-hair that covered the Mishkan. The number eleven represents an addition ("ha'Mosif") to a pre-existing, complete set -- the number ten. The number eleven is mentioned with regard to the Ketores, which was composed of eleven ingredients (see Rashi to Shemos 30:34). Why was the number eleven selected for the production of the Ketores, when the number ten is normally used to represent a spiritual "full set"?
The number eleven is also mentioned with regard to Esav. The Torah (Bereishis 36:40-43) enumerates the eleven Alufim (chieftains) that were born to the family of Esav. Rashi (Bereishis 33:11) points out a basic difference between Yakov's and Esav's outlooks on life. When Yakov described his material status, he exclaimed, "I have all that I need." Esav, on the other hand, arrogantly stated, "I have much more than I need." Esav sees no goals in life. He is not striving to fulfill a particular purpose; rather, he grabs limitlessly to get as much as he can. Yakov, in contrast, lives for a purpose. He strives to fulfill a particular mission, and if he is able to accomplish that mission, he has all that he needs.
The number ten represents completeness, a full integer count. The number ten represents Yakov's purposeful existence. The ideology of Esav, of seeing no limits or goals and of amassing "much more" than one needs, is represented by the number eleven. It indeed is appropriate that his nation originated with eleven chieftains. However, for all of his amassing of wealth, one who follows such an ideology will actually end up with less, not more.
Esav's attitude of having "much more than I need" is represented by the number eleven. All of his additional wealth takes him farther from attaining the true goals of life. Esav, and the arrogant people who follow his way of life, nevertheless can realize that "Kol ha'Mosif Gore'a," that one who adds, takes away. They can realize that "arrogance is a blemish" and can become servants of Hash-m.
This helps to explain the significance of the number eleven in the Ketores. Rashi (Shemos 33:34) explains that only ten of the components of the Ketores are actually sweet-smelling. The eleventh, Chelbena, gives off a putrid smell. Only when combined with the other components does the Chelbena produce a sweet smell. This is to show that when those who repent and pray to Hash-m should not refuse sinners the right to join them in prayer. On the contrary, only when their prayers are combined with the prayers of the sinners will the prayers give off a "sweet scent" before Hash-m (Kerisus 6b). Chelbena, the eleventh component of the Ketores, represents those who follow the ideology of Esav. Ketores shows that when such people realize that they are only an "incomplete eleven," and that their arrogance causes them to be lacking, they can join with the righteous to produce a sweet scent.
Deriving the concept of "Kol ha'Mosif Gore'a" from these three sources in the Mishkan -- the Aron, the Shulchan, and the Yeri'os Izim -- might be alluded to in the verse, "A wise man shall not pride himself in his wisdom, and a strong man shall not pride himself in his strength; a wealthy man shall not pride himself with his wealth. Rather, one should pride himself with this: contemplate and know Me..." (Yirmeyahu 9:22-23). The "Kol ha'Mosif" of the Aron corresponds to the Chacham, the wise man. The "Kol ha'Mosif" of the Yeri'os corresponds to the Gibor, and the Kol ha'Mosif of the Shulchan corresponds to the wealthy man. As Rashi points out, there are three vessels in the Mishkan which have crowns -- the Aron, Shulchan, and Mizbe'ach ha'Ketores. The crowns of the Aron and Shulchan correspond to Keser Torah and Keser Malchus, respectively. The crown of the Mizbe'ach ha'Ketores corresponds to Keser Kehunah (Shemos 30:3). The Kohen, whose essence is dedicated exclusively to the service of Hash-m, corresponds to "know Me." That crown does not need a reminder to refrain from arrogance, since the Kohen's pride comes only from his closeness to Hash-m. That is why the Kohen wears clothes made "l'Kavod ul'Sif'ares," for honor and glory, and the verse says, "va'Yigbah Libo b'Darchei Hash-m" -- "his heart was lifted in the ways of Hash-m" (Divrei ha'Yamim II 17:6), teaching that it is appropriate to take pride in following the ways of Hash-m. (M. Kornfeld)

29b----------------------------------------29b

2) ADMISSION OF DEBT
QUESTION: The Gemara teaches that if a person who has a reputation of being rich admits that he owes money to others, the debts may not be collected in court; his admission is assumed to have been made merely for the sake of making himself look like he is not rich -- "she'Lo l'Hasbi'a Es Atzmo." The Gemara says that, similarly, a person will lie about his wealth so that his children will not think that they are rich -- "she'Lo l'Hasbi'a Es Banav."
Why does the Gemara give these reasons for why his admission is not binding in court? Why does it not give the reason that it gives earlier (29a), where it says that if a person admits that he owes money, he may say later "Meshateh Ani Bach" ("I was joking with you"), provided that he did not designate witnesses to testify about his admission. Conversely, why does the Gemara there not give this reason ("she'Lo l'Hasbi'a") for not accepting his admission?
ANSWERS:
(a) The ROSH and NIMUKEI YOSEF (see also TOSFOS DH Kach) explain that a person may say that he was joking only when another person demands money (Tove'a) from him in court. The confessor-borrower may say that he confessed that he owed the debt only as a joke, since the claimant himself made a foolish claim by creating a debt when no debt existed. He may say that just as the claimant made up a false debt, he replied with a false admission. The Gemara here, in contrast, refers to a person who admits to a debt when no one demands such a debt from him.
In the case of the Gemara here, in which no one is demanding money from him, there is a different way for the person to defend his admission. He may say, "I admitted only to make myself look poor." In the case earlier, however, in which someone demands money from him, his admission could not have been to make himself look poor, since he would not have waited for someone to claim money from him in order to make himself look poor.
The HAGAHOS MAIMONIYOS (Hilchos To'en v'Nit'an 6:40) asks that according to these Rishonim, how does the Gemara earlier (29a) learn from the Mishnah that a person may say "Meshateh Ani Bach"? How does the Gemara know that the Mishnah is discussing a case in which the person admitted only after someone demanded money from him, and that he may say "Meshateh Ani Bach" under such circumstances? Perhaps the Mishnah is discussing a case in which he admitted on his own accord, without any other person demanding money from him, and the reason why he may retract his admission is that he may say that he did it "she'Lo l'Hasbi'a"!
The HAGAHOS MAIMONIYOS answers that since the Mishnah there does not specify the case, it implies that in all cases a person may retract his admission, whether or not someone demanded money from him.
(b) The RAMBAM (Hilchos To'en v'Nit'an 6:7 and 7:1, as explained by the KESEF MISHNEH) gives an alternative distinction. If the person admits that he owes money in the presence of the person to whom he claims he owes, then whether or not the person demanded money from him he cannot say that he admitted merely in order to make himself look poor. If that was his purpose, he should not have done it in a way that would have brought his admission to the attention of the supposed lender. That is why, in the case of the Gemara earlier (29a), he cannot say that he merely was trying to make himself look poor. In the Gemara here, on the other hand, the person admitted to owing the money not in the presence of the supposed lender. Therefore, he may say that he merely was trying to make himself look poor. He cannot say, however, that he was trying to fool the other person, because there is no supposed lender to fool in his presence at the time of his admission.