Rambam - 1 Chapter a Day

The party who receives the extra profit is not required to return it, nor is. the exchange nullified.
The Kessef Mishneh explains the rationale for this ruling. Leviticus 25:14, which mentions the prohibition against ona’ah, speaks about a sale. An exchange of articles or livestock is not described with that term.

Other versions of the Mishneh Torah read “armor.”

Generally, the necklace (armor) and the donkey are considered to be much more valuable.

The Ra’avad objects to the Rambam’s ruling, maintaining that if the person is concerned with the value of the article he exchanges (as the Rambam states with regard to the fruit), the laws of ona’ah apply even if he exchanges one animal for another. And if he is not concerned with the article’s value, even if he exchanges one pile of fruit for another the laws of ona’ah do not apply. The Maggid Mishneh and the Kessef Mishneh justify the Rambam’s ruling, stating that even if one evaluates articles, the laws of ona’ah do not apply to their exchange.

See Chapter 5, Halachah 3, which explains that although generally the kinyan of chalifin does not apply with regard to coins, an exception is made in such an instance, because rather than deal with them as one would deal with legal tender, the seller dealt with them as mere objects.

I.e., following the guidelines given in Halachot 2 and 3 of the previous chapter.
The Kessef Mishneh states that the wording the purchaser uses is significant. If, as the Rambam says, he states: “Sell your cow to me for these,” the transaction is considered like a sale, and the laws of ona’ah apply. If, however, he states “Exchange your cow,” it is not considered to be a sale, and the laws of ona’ah do not apply.

See Chapter 21, Halachah 2.
The Tur does not accept this ruling, and although the Shulchan Aruch (Choshen Mishpat 227:19) quotes the Rambam’s decision, the Ramah cites the view of the Tur.

If, however, a person carries out a small business from his home, it is considered to be an ordinary sale and the laws of ona’ah do apply.

The Maggid Mishneh explains that the Rambam is speaking only of exorbitant gain acquired by the seller. If the purchaser takes advantage of the seller, the laws of ona’ah do apply.

When quoting this law, the Shulchan Aruch (Choshen Mishpat 227:23) adds two points:
a) Even if the homeowner is in difficult financial straits and thus must sell his personal belongings, he can still be expected to demand a high price for them.
b) This ruling applies only when the purchaser buys the article from the homeowner. If, however, the sale is being conducted by an agent, and the purchaser does not know that he is buying someone’s personal goods, the laws of ona’ah do apply.

For the reasons explained by the Rambam in the next clause.

The amount of unfair gain is not explicitly mentioned.

I.e., the rationale why this condition is not binding is that a person may waive money that is rightfully his. Nevertheless, for such a commitment to be binding, he must know the exact amount that he is forgoing. (See a similar ruling in Chapter 11, Halachah 16.) Otherwise, we assume that the commitment was made facetiously, without sincere intent.

Sefer Me’irat Einayim 227:38 maintains that the Rambam [and the Shulchan Aruch (Choshen Mishpat 227:21), which quotes his wording] maintain that the transaction is nullified, because the person is making a condition that countermands the Torah’s commandment. The Torah rules that ona’ah applies, and no condition can nullify that truth.
Rashi (in his commentary on Bava Metzia 51a) gives a different rationale: The transaction is being conducted under false pretenses, because the person’s statements are not true. There is unfair gain in this instance.
The difference between these perspectives is not one of theory alone. According to the Rambam, if the article is worth one sixth more than the price paid for it, the transaction is binding and the purchaser must reimburse the seller for the unfair gain. According to Rashi, however, since the transaction was conducted under false pretenses, it is nullified entirely.

In the previous instance, the person is making a condition that the laws of ona’ah do not apply. He has no authority to make such a condition. In this instance, he is saying that “Although the laws of ona’ah apply, and this money is rightfully mine, I am forfeiting my claim to it.”
This is one of the distinctions between cases of financial law and cases involving marriage and divorce. In cases of financial law, should a person individually accept a condition that countermands a commandment of the Torah, as above, the condition is binding.

For he has not stated that the Torah prohibition does not apply, but that despite the Torah prohibition, the purchaser will not hold him liable. And he has defined specifically the amount of money that the purchaser is waiving on his behalf. See, however, Chapter 5, Halachah 11.

100 zuz.

The Siftei Cohen 227:15 quotes an opinion that states that similarly, the transaction is not nullified if the unfair gain is more than a sixth, and that even if the purchaser takes unfair advantage of the seller, the laws of ona’ah do not apply.

The Maggid Mishneh explains that in this instance, the purchaser does not consider the worth of the article, but rather the words used by the seller.

I.e., preparing the object for sale did not involve paying merely its purchase price, but also these other secondary costs.

If he were permitted to add this amount, he would be taking profit both as a worker and as a seller. This is not considered to be “faithful” conduct.

And a gentile is not considered to be “your brother.”
The Lechem Mishneh notes that the verse uses two terms, amitecha, “your colleague,” and achiv, “his brother.” Bechorot 13b interprets amitecha as excluding a gentile, and achiv as excluding “consecrated property.” (See the following halachah.) He notes that the Rambam switches the proof-texts used by the Talmud.
The rationale for the switch can be explained as follows: When excluding “consecrated property,” the fundamental point is that the verse is referring to a human being. Amitecha, “your colleague,” communicates that concept. The exclusion of a gentile, by contrast, comes because this law is one of the unique dimensions of the bond of brotherhood that exists among the Jewish people. This concept is more appropriately communicated by the term achiv.

See Hilchot Melachim 10:12.

Tosefot Yom Tov notes that although the Rambam’s ruling is quoted from the Mishnah (Bava Metzia 4:9), the Rambam changes the order of the subjects from that listed in the Mishnah. The order employed by the Rambam is more closely related to the explanation of the derivation of these concepts.

Generally, when used without a modifier, this term refers to Canaanite servants. In this instance, as evidenced by Halachah 15, the implication is much broader.

I.e., the Temple treasurer sold consecrated property to enable the funds to be used for the Temple’s purposes; alternatively, a person sold an animal that he had consecrated as a sacrifice, but that was disqualified because of a blemish.
Note Sefer Me’irat Einayim 227:49, which explains that this exclusion applies only to articles consecrated to the Temple or the altar, and does not apply to gifts to charity in the present age.

The Jerusalem Talmud (Bava Metzia 4:9) states that when landed property is sold for more than twice or less than half its value, the transaction is nullified. This opinion is also quoted by several of the later Geonim. By giving this example, the Rambam emphasizes that he does not subscribe to that view.
The Shulchan Aruch (Choshen Mishpat 227:29) quotes the Rambam’s ruling, while the Tur and the Ramah mention the opinion cited in the Jerusalem Talmud.

Thus, the sale of a promissory note does not involve the transfer of ownership hand to hand. See Chapter 6, Halachah 12 and notes.

For in such sales, one is not dealing with “a colleague.” See the notes on the previous halachah.

I.e., the exclusion of these four entities, and in a more general sense, all the laws of ona’ah.

The rationale is that although a person is usually willing to forgo up to a sixth of the value of an article, that is when he makes the decision himself.

The Maggid Mishneh states that this applies even to an agent of the court.

For the principal will say: “I charged you with acting for my benefit, not with acting for my harm” (Kiddushin 42b).
The Shulchan Aruch (Choshen Mishpat 227:30) states that the above applies when unfair advantage is taken of the agent. If the agent takes unfair advantage of the other party, there is a difference of opinion among the Rabbis. Some say the ordinary laws of ona’ah apply, while others say that the transaction is nullified if the slightest amount of unfair gain is taken. [Note, however, the statements of the Bedek HaBayit (Choshen Mishpat 109).]

This expression refers to a law that the Rambam derived through his own logic without an explicit source in previous Rabbinic literature.

See the following halachah. This distinction applies even when the guardian is appointed by the court (Maggid Mishneh).

Note Hilchot Malveh V’Loveh, Chapter 12, where the Rambam mentions the order of announcements that must precede the sale of the property of orphans.

Our translation follows the understanding of the Tur and the Shulchan Aruch (Choshen Mishpat 109), and the commentary of the Meiri on Ketubot 99b. Rabbenu Nissim and others interpret this as meaning that the other party to the transaction desires that the transaction stand.

Since the purchaser could not retract had this transaction been concluded with an ordinary individual (see Halachah 8), he cannot retract when the transaction is concluded by a court.
The Ra’avad differs with this ruling, maintaining that even when a transaction is concluded by the court, the purchaser can retract. The rationale is that a person who enters into a transaction being conducted by a court expects that transaction to have been conducted fairly. The Maggid Mishneh quotes the Ramban, who supports the ruling of the Rambam.
The Shulchan Aruch (Choshen Mishpat 109:5) quotes the Rambam’s ruling, while the Tur and the Ramah quote that of the Ra’avad.

With regard to landed property, as mentioned above, the laws of ona’ah do not apply, and the division is allowed to stand no matter how unjust it is.

There is an opinion in Bava Metzia 58b that explains that since oxen work in teams and pearls are combined with others in jewelry, there are times when a person will purchase an animal or a pearl for more than its value, because it is appropriate to be combined with others. The Rambam does not accept this view.

There is an opinion (Bava Metzia 58b) that the laws of ona’ah do not apply when one sells a sword or a horse in wartime, because by purchasing them one can save one’s life. The Rambam does not accept this view.

Although the value of a Torah scroll cannot be determined in financial terms alone, it is still considered comparable to other movable property, and the laws of ona’ah apply.

Mentioned in Halachah 8.

I.e., in contrast to a sale carried out by an agent (Halachah 9) or a court (Halachah 10).

Note the contrast to Halachah 18.

This parallels the concept stated in the previous halachah. Just as there is no difference between the sale and the rental of landed property, so too, there is no difference between the purchase of a person’s service for all time and hiring him for a brief period.

As stated in Halachah 8.
There are commentaries that ask how an equation can be drawn between a Canaanite servant, whose physical person is owned by his master, and a Jewish worker, who is his own master, and for that reason has the privilege of terminating his employment at any time.
The Machaneh Efrayim (Sechirut Po’alim 1) explains that although a worker has the above privilege, until he exercises it and actually terminates his employment, his physical person is owned by his employer. (See also Sefer Me’irat Einayim 227:59.)

The Kessef Mishneh explains that instead of the employer agreeing to pay a worker a daily or hourly wage, he contracted him to sow the entire field for a lump sum. As stated in Halachah 18, the laws of ona’ah apply with regard to a contractor, while they do not apply with regard to a worker paid wages (Halachah 15).

Using seeds belonging to the owner of the field.

The intent is not that there is a dispute regarding the quantity of seed used, but that the contractor claims that only a certain number of seeds are necessary, and the witnesses testify that the standard practice is to sow a greater number (Maggid Mishneh, explaining the Rambam’s interpretation of Bava Metzia 56b).

I.e., he is considered as having been contracted for the seeds, which are movable property. Thus, the laws of ona’ah do apply.

I.e., he is considered as having been contracted for the landed property, in which case the laws of ona’ah do not apply.

For, as stated in Hilchot To’en V’Nit’an 5:1, a person is never required to take an oath required by Scriptural Law with regard to disputes involving landed property.

Hence, just as the laws of ona’ah apply with regard to the sale of these articles, so too, they apply with regard to their rental.

For unlike a purchaser, who has the article in his possession and can show it to a colleague for evaluation, a long time may pass before a renter sees an equivalent article and has the opportunity to have the price for its rental appraised (Maggid Mishneh; Sefer Me’irat Einayim 227:65).

As mentioned previously, this expression indicates a ruling that is not explicitly mentioned in earlier sources, but rather derived by the Rambam through his inductive reasoning. The Rambam distinguishes between a contractor and a worker. (See Halachah 15.) For unlike a worker, the contractor is not selling his time, but rather the product of his efforts.
In this instance, the Ramban and others differ and maintain that just as the laws of ona’ah do not apply with regard to a worker, they do not apply with regard to a contractor.

The intent is that if unfair advantage is taken of either of them, that person may retract. The person who takes unfair advantage may not retract, as stated in Chapter 12, Halachah 4 (Sefer Me’irat Einayim 227:67).

Just as a seller does not always have the article available so that he can have it appraised (Chapter 12, Halachah 6), so too, in this instance, there is not always an opportunity to appraise the contractor’s efforts.