Rambam - 1 Chapter a Day

As defined in the following halachah.

For besides the financial dimensions of the matter, taking a false oath involves the desecration of the honor of God’s name. See Hilchot Sh’vu’ot 1:16, which states: “The entire world trembled when the Holy One, blessed be He, told Moses: ‘Do not take the name of God, your Lord, in vain’ (Exodus 20:7).”

As explained in Hilchot Sh’vu’ot 1:1-3, a sh’vu’at bitui is a false oath taken by a person with regard to his past actions - i.e., he says that he did something that he did not do, or he says that he did not do something that he did do. Alternatively, it refers to an oath that the person will or will not do something in the future, and the person violates that oath.
The commentaries note that in his commentary on Sh’vu’ot 31b, Rashi speaks of the person being considered to be suspect only when he takes an oath that is false, but not if he later performs an act that violates his oath. According to the Rambam, however, it can be explained that just as a person is disqualified for committing any sin, he is disqualified for performing an act that violates an oath (Maggid Mishneh).
The Rivash (Responsum 311) explains that even the Rambam would accept Rashi’s ruling. For in Hilchot Edut 10:2, the Rambam rules that a person is disqualified as a witness only when he transgresses a prohibition that is punishable by lashes. Since lashes are not administered for violating a sh’vu’at bitui when a person took an oath that he would or would not perform a particular deed, a person who performs such a violation is not disqualified from taking an oath in the future. The Shulchan Aruch (Choshen Mishpat 34:5, 92:2) quotes both opinions without deciding in favor of either.

Sh'vuat ha'edut refers to a situation where witnesses know of a matter that pertains to a claim that one litigant lodges against another. The witnesses refuse to testify, and the litigant has them take an oath that they do not know of any pertinent testimony (ibid. 1:12).

Sh'vuat hapikadon refers to a situation where a person has money that belongs to another person and denies it under oath (ibid. 1:8).

The Rambam defines four types of unnecessary oaths: a person who takes an oath that an object whose identity is known is in fact something else - e.g., a person who takes an oath that a man is a woman; one who takes an oath that an object whose identity is known is in fact that object - e.g., a person who takes an oath that the heavens are the heavens; one who takes an oath that he will not perform a mitzvah - e.g., he swears that he will not put on tefillin; or he takes an oath that he will perform an action that it is impossible for him to do - e.g., he takes an oath that he will go three days without sleep (ibid. 1:4-7).
Such a person is considered to be liable to take a false oath, because - even though the oath he originally took was not false - the fact that he could deal so flippantly with God’s name, indicates that there is the possibility that he will lie.

For just as he took a false oath in the past, it is possible that he will take a false oath in the future.
Note the Shulchan Aruch (Choshen Mishpat 92:2), which states that a person is placed in this category even for violating a ban of ostracism declared by the community.

See Hilchot Edut, Chapter 12.

See Hilchot Gezelah Va’Avedah 4:7.

Gambling is not considered to be theft according to Scriptural Law. Nevertheless, according to Rabbinic Law, if a person has no other occupation than gambling, he is disqualified as a witness (ibid. 10:4).

A person is disqualified as a witness for willfully performing a transgression. We assume that if he will willfully commit any other transgression, he might also take a false oath.

For we do not accept testimony a person gives against himself, and he is not disqualified as a witness on that basis (Hilchot Edut 12:2).

I.e., although he is not halachically disqualified, we take precautions lest his statements be true.

E. g., in a situation where a person is arbitrarily choosing witnesses, he should not choose this person.

Instead of reversing the obligation to take the oath, as stated in the following halachah.
The Maggid Mishneh quotes the opinion of the Remo who states that this law applies only with regard to a defendant who is required to take an oath to defend his property. When, by contrast, a plaintiff who has the opportunity to take an oath to expropriate property from the defendant admits that he should be disqualified from taking an oath, we in fact disqualify him. The Shulchan Aruch (Choshen Mishpat 92:5) quotes this ruling.
The Shulchan Aruch also quotes the opinion of the Tur, who states that when a defendant admits to being disqualified, the option is given to the plaintiff. If he desires to take an oath to support his claim and then collect his due, he is given that opportunity. The Siftei Cohen 92:6 clarifies that this applies only to a Scriptural oath and not a sh’vu’at hesset.

This excludes a watchman, as the Rambam proceeds to explain.

I.e., a severe Rabbinic oath that resembles a Scriptural oath.

And thus, the plaintiff also does not have the option of taking the oath.

For when a person is required to take a Scriptural oath, it is as if he is under obligation to the plaintiff - and with the oath, he absolves the obligation. If he does not absolve the obligation with an oath, he must absolve it financially.
It must be emphasized that there is another opinion in Sh’vu’ot 44b, 47a, the source for this halachah, which states that the money in question should be divided. I.e., since there is an unresolved doubt regarding to whom it is due, we divide it. This difference of opinion was perpetuated in the generations after the Talmud, with Geonim and Rishonim taking both positions. In the later generations, the Shulchan Aruch (Choshen Mishpat 92:7) follow the Rambam’s view, while the Tur and the Ramah adopt the other position.
The Ramah also quotes an opinion that maintains that the Rambam’s position is followed only when at the outset, the plaintiff did not know that the defendant was suspect. If, however, he knew that he was suspect when he entered into a business agreement with him, he cannot lodge a claim against him that would require him to take an oath. For if that were the case, a person who is suspect would constantly be at the mercy of others.
See also the Rambam’s Commentary on the Mishnah, where he explains that the defendant may have a conditional ban of ostracism issued to protect his rights.

The Siftei Cohen 92:11 states that the same laws apply when a plaintiff lodges a claim against the defendant on the basis of the testimony of one witness, when the plaintiff himself does not know of the matter.

According to the Rambam, in such a situation, the defendant would be released from his responsibility. The Remo argues that even in such a situation, the defendant is required to pay the claim.

In which instance, he is liable unless the article is returned intact.

E. g., a hired worker, a person who was injured, a person from whom property was stolen or the like.

The Maggid Mishneh states that although this law is not stated in the Talmud, it is a product of deduction. If our Sages will not allow a person who is suspect of taking a false oath to protect his resources by taking an oath, certainly they will prevent such a person from taking an oath so that he can collect property from others.
The Lechem Mishneh explains that there is no reason to amplify a person’s legal power because he is suspect to take a false oath. According to Scriptural Law, the person has no right to collect his claim. Although our Sages gave him the right to take an oath and collect his claim, it is unthinkable that they would grant him what he claims without requiring an oath from him.

By admitting that a portion has been paid (Hilchot Malveh V'Loveh 14:1).

I.e., plaintiffs who have the right to collect their claim according to Scriptural Law - e.g., a person who seeks to collect from heirs.

It is suggested that the text should read “or,” rather than “and.” Thus, it would refer to an instance where a defendant claims to have paid the debt and demands that the plaintiff take an oath (ibid.:2). This version appears correct because even without the defendant’s asking, when a plaintiff impairs the legal power of a promissory note, he is required to take an oath.

The Ra’avad differs with this ruling, maintaining that if the authenticity of the signatures of the witnesses to the promissory note is validated, the bearer is allowed to collect the debt stated in the promissory note without taking an oath. His rationale is that the obligation established by a promissory note has the power of Scriptural Law. Although the Rabbis instituted a safeguard and required that an oath be taken, their intent was not to disqualify the promissory note. Hence, in a situation where the safeguard cannot be put into effect, it is ignored.
The Maggid Mishneh explains that the Ra’avad does not differ entirely with the principle stated by the Rambam and would accept it with regard to cases involving a paid worker, or a claim of theft or injury or the like. When, however, a valid promissory note is involved, the Ra’avad maintains that the promissory note should not be disqualified. The Shulchan Aruch (Choshen Mishpat 92:9) quotes both opinions, but in (Choshen Mishpat 82:8, the Shulchan Aruch writes that the Ra’avad’s view is logical. See the Siftei Cohen 92:14, who brings further support for the Ra’avad’s perspective.

E. g., a partner or a sharecropper.

Because he is suspect to take a false oath.

Instead, the defendant is freed from liability without taking an oath.

Perhaps the Rambam adds this point to emphasize the strength of the argument. Even those authorities who rule more stringently in Halachah 4, rule leniently here.

I.e., as stated in Halachah 4, since the plaintiff does not have a definite claim, there is no way that he can take an oath.

Although the responsibility to take a sh'vu'at hesset can be reversed (Chapter 1, Halachah 10), that is left to the choice of the defendant. We do not arbitrarily force that decision upon him.

For according to Scriptural law, the defendant would be released without an oath.

Scriptural Law gives the defendant the stronger position. Allowing the plaintiff the opportunity to take the oath would reverse that position entirely.
The Shulchan Aruch (Choshen Mishpat 92:11) emphasizes that a conditional ban of ostracism is passed against anyone who denies a claim lodged against him.

Although a defendant usually has an option of reversing the responsibility to take an oath, an exception is made in this instance, because of the reason mentioned by the Rambam. This ruling does not have an explicit source in the prior Rabbinic literature, but is instead a product of deduction (Maggid Mishneh).

By reversing the responsibility for the oath, the defendant would be hoping to be absolved without taking an oath.

See Chapter 5, Halachah 10.

The Maggid Mishneh writes that this law is also a product of deduction and is not explicitly stated in the Talmud.

I.e., if we are speaking of a Rabbinic oath that enabled the suspect person to collect his claim from the defendant - e.g., a worker or a person who claims injury or theft.

I.e., if we are speaking of a Scriptural oath that enabled the suspect person to free himself from liability.

With regard to lashes, Deuteronomy 25:3 states: “Your brother will be degraded in your eyes.” Makkot 23a states: “Once he is ‘degraded,’ he is your brother” - i.e., his position is no longer lowered because of his sin.

In this context, by repentance the Rambam does not mean merely regret over the evil he has performed and a commitment to do good in the future (the definition he gives in Hilchot Teshuvah 2:2). Instead, that resolve must be accompanied by the performance of an act that shows the sincerity of that commitment, as indicated by Hilchot Edut 12:5-10.
The Rambam’s statements appear to imply that receiving lashes alone is not sufficient to restore a person’s status. This raises a question, for the Rambam states (ibid.:3-4):
If two [people] came and testified that he repented and showed remorse or he received lashes, he is acceptable.... Whenever a person was liable to receive lashes, his status is restored whether he repents or received lashes in court.
The Lechem Mishneh maintains that the apparent contradiction can be resolved by interpreting our halachah as meaning “he received lashes or repented.” In his Kessef Mishneh (in his gloss on Hilchot Edut), Rav Yosef Karo explains that from the continuation of the Rambam’s words in Hilchot Edut, it is apparent that a person who committed a sin that did not bring him financial benefit is restored to his previous status after receiving lashes. If, however, the sin involved financial benefit, he must also repent. Rav Karo applies this understanding as halachah in his Shulchan Aruch (Choshen Mishpat 34:29).

We believe the testimony of this pair of witnesses even though it renders the oath as false. Although there is a difference of opinion concerning this matter in Bava Kama 106a, the Rambam follows the opinion of Rav Nachman, one of the leading sages in the midst of the generations of Amora’im.
Although a sh’vu’at hesset is a Rabbinic institution, if witnesses testify that a person took a false sh’vu’at hesset, that person is disqualified from taking Scriptural oaths in the future (Meiri).

Hilchot Sh’vu’ot 1:9; 11:20; Hilchot Gezelah Va’Avedah 7:8.

Whenever the Rambam mentions “an additional fifth,” his intent is a fifth of the new total. For example, if the false oath was taken with regard to four zuz, the defendant must pay five.
As stated in the above sources, a person who takes a false oath is also required to bring a guilt offering. Perhaps the Rambam omits mention of this, because he is speaking about the present era when sacrifices may not be brought (Or Sameach).

For his word, even when supported by an oath, is not powerful enough to counter the testimony of witnesses or a valid promissory note.

For it is possible that he did pay. Although his word is not accepted, it is not necessarily deemed a lie.

If they testified that he did not pay, their testimony would be in direct contradiction to his statements, and he would be disqualified.

This also would represent a direct contradiction.