Maimonidian Qabbalah – Recap

Talking it over with some friends, it became clear that my posts on this topic required an overview. The explanation got buried among the proofs, and it’s therefore hard to follow the flow of the essential points. It all started with my considering the Leshem. Here we have a mequbal whose works follow the Vilna Ga’on’s approach to Qabbalah and yet also cites the Rambam frequently. This led me to think about the points hared in common between the Rambam’s philosophy, which is usually thought of as Artistotilian Rationaism, and Qabbalah.

  1. According to the Rambam, creation is via a series of angels. First is G-d, the only One who exists without any contingencies, then the highest level of angels, who in turn are the causes of the next level, and so on, down until the Celestial Spheres and finally the physical substances of this world. Each level more contingent than the prior. (Part I)
  2. Angels are both forms without substance and thought independent of matter.(We then explored the identity of form and thought, and how in information theory too, a bit is one aspect of the form, and totally unrelated to the substance or even other aspects of the object’s form.) So, we can equally discuss of a chain of forms down from the most abstract downward into physical substance. And we can also describe this chain of angels as G-d having a thought, who has a thought, who has a thought, etc…
  3. The Rambam also understands events as being initiated by intellects (in consonance with Aristotelian physics). In the case of Divine Will, angels are the intellects that mediate between His Will and physical motion and change. Thus, angels are not only definable as links in the causal chain of the existence of objects, but also in the occurrence of events. (Part III)
  4. Qaballah refers to a Divine Light which is ne’etzal, willfully emanated by G-d (Part II). Unlike forms, Light fills space, thus adding to Qabbalah two concepts not in the Rambam’s discussion:
    1. A hierarchy of olamos, universes that run from concrete physical existence to one step below the Divine.
    2. Tzimtsum, the restriction of that Light. If we view Hashem’s power of creation as  a Light, then the pure white undifferentiated light of G-d must be filtered and differentiated for various things to exist. Creation via tzimtzum is like the projection of a movie in a theater. The film stands between the light and the screen, blocking various parts of the light, narrowing the colors and amount of light that reaches each portion of the screen.
  5. Still, the Leshem identifies this Light with the same concepts as the Rambam’s understanding of existence. The light bridges each world’s forms to those of the world below. The substances of one world are the forms of the world below. The Light actually shines through twice to the next world twice: once as the substances becomes its forms, and a second time as those forms take on substance.
  6. Thus, according to the above, each world contains a set of truths more abstract than the one below. This concept is echoed in Rav Dessler’s explanation of the Maharal’s understanding of miracles. According to the Maharal, the difference between living in a world of natural law or one of miracles depended upon the spirituality of the viewer’s perspective. Even to the extent that two people experience different realities. Rav Dessler elaborates that this is the very difference between worlds. The person for whom the laws of Justice, Morality and Spirituality are more absolute than those of physics will impose that order on the world of his perceptions. And so, miracles will actually violate natural law in conformance with that perception (Mind, Perception, and Metaphysics).
  7. According to the Rambam as well, the prophet is someone who raises his perception to that higher plane. This is the basis of his dispute with the Ramban about the nature of prophecy. According to the Ramban, prophecy is a message relayed via vision. But according to the Rambam, prophecy is a perception of events at a higher plane of reality.Thus, the Rambam says that Avraham’s three visitors came in a prophetic vision and yet actually did save Lot from the real destruction of Sodom. The Abarbanel explains that even though he believes that angels can only be seen through prophetic vision (since they are not physical, and therefore can’t be seen by physical vision), the angels seen in that vision are real, and their actions are real.In contrast, the Ramban has no problem believing that the Man in the throne seen by the elders at Mt Sinai, and by Yirmiyahu and Yechezqeil in their visions of the Divine Chariot actuall was G-d. Because to him, nothing in a vision is real — the Man is simply a symbol in a message, representing G-d. However, to the Rambam’s understanding of prophecy, identifying the Man with G-d would be idolatrous, as it would mean that from the more abstract perspective, G-d had a body. Rather, Maimonides understands the Man as being Kavod Nivra, Created Glory. An entity created to embody G-d’s Kavod, and not Hashem Himself. (Aspaqlaria [title post]).
  8. This distinction — whether the prophet is one who tries to receive G-d’s message or develop his own unity until he himself is on a higher plane, is the root of the “Forks in the Hashkafic Road” category.)
  9. People have this ability to see things at different planes of abstraction. And, if sufficiently holy, to actually lift our perception to that of other worlds. We are unique in this way. Angels are static. Each are on its level, depending upon the type of angel. Each is a slice, one plane along the Divine Light. The physical is the lowest plane of reality. The human soul, however, extends along the entire dimension. We are unique in this way. (Form and InFORMation)
  10. A person’s consiousness is always aware of three things — the plane of abstraction it is focused on, the aspect of the soul on the plane immediately below it, and the aspect of the soul immediately above. This is the root of Naran (see blog category). Since Adam’s expulsion from the garden, people spend most of their existence (barring moments of prophecy or miracle) such that their awareness is from the perspective of the physical world, their lower desires are those of the body, and their loftier ones are those of the Olam haYetzirah, which Rav Dessler (above) defined as the one where the laws of Justice, Kindness and Spirituality operate.
  11. The relationship between soul and brain is therefore NOT as two distinct entities. Rather, the final link in the soul’s chain of forms is embodied in the brain. It is the soul, as it is manifest on the physical plane.
  12. The Nefesh haChaim writes that physical action causes metaphysical change only through people. Only people combine the forces of all the worlds, therefore only through the human soul do changes in one world carry through to others. This is akin to Rav Dessler’s explanation of miracles, a generalization of the idea. Actions change perception, and that’s what changes the underlying metaphysics in how the universe responds. Thus, according to all of the above, in this misnagdic qabbalah, a mezuzah can not protect the home. It’s the act of keeping the mitzvah of mezuzah which impacts the soul and it is that which brings protection to the home. If one does the mitzvah perfectly, checking it as recommended, etc…, and unbeknown to them a letter happened to crack off the parchment, there is no reason to assume the home is any less protected than had the mezuzah been whole.

One more concept not yet raised in this discussion:

  • Somewhere early along this chain of forms/ideas/angels is Chessed. As Hashem lacks nothing, a common observation (made by R’ Saadia Gaon and the Ramchal, to bring two distant examples among many others) is that the only ones to benefit from Creation are the created. Creation occured because “it is the nature of Good to have someone to whom to bestow that good”.
  • However, the ultimate Good would be to share in G-d’s Image, and thus to be able to define ourselves, jusr as G-d Himself is not shaped by external forces (in a more absolute sense).
  • Thus, growing out of Chessed is Gevurah, Divine Restraint, holding back to allow us to make our own mistakes, and also to complete ourselves as we see fit.
  • According to the Malbim (on Dani’el) this is the relationship between Micha’el (Chessed) and Gavriel (Gevurah). But then, we already established that angels are forms (abstractions) / intellects.

(If you see in this the sketching of a pattern that could be carried through to all ten Sephiros as they appear in the Eitz Chaim, that is intentional.)

This shows where the notion of Divine Justice as developed in the first section of my Aseres Yemei Teshuvah reader (where you can find these bullet items developed in far more detail) fits in relation to this larger model. Just as, along the way, I tried to give similar context to the model of the psyche developed on this blog, prophecy, miracles, the split between Chassidim and Misngdim, and a number of my other recurring topics.

Qitzur Shulchan Arukh – 183:4

ד: אָסוּר לִמְסֹר ישְׂרָאֵל בְּיַד גּוֹיִם, בֵּין גּוּפּוֹ בֵּין מָמוֹנוֹ, בֵּין בְּמַעֲשֶׂה בֵּין בְּדִבּוּר, לְהַלְשִׁין עָלָיו אוֹ לְגַלוֹת מַצְפּוּנָיו. וְכָל הַמּוֹסֵר, אֵין לוֹ חֵלֶק לָעוֹלָם הַבָּא. וַאֲפִלּוּ רָשָׁע וּבַעַל עֲבֵרוֹת, אָסוּר לְמָסְרוֹ לֹא גוּפּוֹ וְלֹא מָמוֹנוֹ, וַאֲפִלּוּ הוּא מֵצֵר לוֹ וּמְצַעֲרוֹ תָמִיד בִּדְבָרִים. אֲבָל אִם חֲבֵרוֹ מוֹסֵר אוֹתוֹ וְאִי-אֶפְֹשָר לְהַצִּיל אֶת עַצְמוֹ אֶלָּא עַל יְדֵי שֶׁיִמְסֹר אוֹתוֹ, מֻתָּר

If it prohibited to surrender on a Jew to the control of non-Jews, whether bodily or with respect to his money, whether through action or speech, to inform on him or to reveal his hiding place. Whomever surrenders [a fellow Jew] has no place in the World to Come. Even someone who is evil and a master of sin, it is prohibited to turn him over, neither his body or his money. Even if he is a troublemaker to him and causes him problems constantly with his words. However, if his friend turns him in, and there is no way to save himself except through turning in [the informer] it is permitted.

None of the above applies to eliminating someone who is dangerous to the community who can not be removed in some other way. In other words, while informing on a fellow Jew to non-Jewish authorities is prohibited, allowing a child molester (for example) to continue posing a danger to our children is a greater prohibition. If someone finds themselves in this situation, one must consult with communal leaders to see if the authorities are a necessary means of getting him off the streets, and if so, speak with rabbis about the permissible way to do so.

Qitzur Shulchan Arukh – 183:3

ג: וְכֵן חֵיל מֶלֶךְ שֶׁבָּא לְעִיר, וּבְנֵי הָעִיר מְחֻיָּבִים לָתֵת לָהֶם אַכְסַנְיָא, אָסוּר לְאֶחָד לִתֵּן שָׂכָר לְשַֹר הַחַיִל לְפָטְרוֹ, כִּי עַל יְדֵי זֶה יִגְרֹם נֶזֶק לְישְׂרָאֵל אַחֵר. וְכֵן בְּכָל שְׁאָר עִנְיְנֵי מִסִּים, אָסוּר לְהִשְׁתַּדֵּל אֵצֶל הַשַּׂר לְפָטְרוֹ, אִם עַל יְדֵי זֶה יַכְבִּיד עַל אֲחֵרִים . וְהָעוֹשֶׂה כֵּן, נִקְרָא מָסוֹר

Similarly, if the king’s army enters the city and the people of the city are obligated to provide them hospitality, one is prohibited to pay off the general of the troups to get him out of it. Because through this he will cause damage to someone else. Similarly in all other matters of taxes, it is prohibited to make efforts by the general to release him, if through this [the tax] will be heavier on others. And one who does this is called an “informer”.

Qitzur Shulchan Arukh – 183:2

ב: אֲפִלּוּ מִי שֶׁבָּא אֵיזֶה נֶזֶק עָלָיו, אָסוּר לְסַלְּקוֹ מֵעָלָיו, אִם עַל יְדֵי זֶה יִגְרוֹם שֶׁיָבוֹא עַל חֲבֵרוֹ, כִּי אָסוּר לְהַצִּיל אֶת עַצְמוֹ אֲפִלּוּ בִּגְרַם נֶזֶק מָמוֹן שֶׁל חֲבֵרוֹ. אֲבָל קֹדֶם שֶׁבָּא הַנֶּזֶק עָלָיו, מֻתָּר לִדְחוֹתוֹ שֶׁלֹּא יָבוֹא עָלָיו, אַף-עַל-פִּי שֶׁעַל יְדֵי זֶה יָבוֹא עַל חֲבֵרוֹ. כְּגוֹן אַמַּת הַמַּיִם שֶׁבָּאָה לִשְׁטֹף שָׂדֵהוּ, עַד שֶׁלֹּא נִכְנְסָה לְשָׂדֵהוּ, מֻתָּר לִגְדֹּר בְפָנֶיהָ, אַף-עַל-פִּי שֶׁעַל יְדֵי זֶה הִיא שׁוֹטֶפֶת שְׂדֵה חֲבֵרוֹ. אֲבָל מִשֶּׁנִּכְנְסָה לְשָׂדֵהוּ, אָסוּר לְהוֹצִיאָה בְעִנְיָן שֶׁתַּגִּיעַ לִשְׂדֵה חֲבֵרוֹ, שֶׁכֵּיוָן שֶׁהַנֶּזֶק מֻטָּל עָלָיו, אֵינוֹ רַשַׁאי לְסַלְּקוֹ מֵעָלָיו וּלְהַטִּילוֹ עַל חֲבֵרוֹ

Even someone who incurred damages on himself he can not remove it from himself if through this he will cause [damages] to come upon someone else. Because he can’t save himself even through indirect causing his friend monetary damages. However, before he incurs the damages, he may push it off that it won’t come upon him, even if through this it will be incurred by his friend. For example, if a stream of water approached [threatening] to flood his field, while it hadn’t yet entered his field, it it permitted to place a damn before it even though through this it will flood his friend’s field. However, once it entered his field, it is prohibited to remove it in a way that it would enter someone else’s. Since the damage already occured, it is inappropriate to divert it from him and place it on his friend.

All else being equal, one may save their own first. However, if I already incurred damages, then all else isn’t equal. I’m merely using my misery as an excuse to share it with someone else.

Qitzur Shulchan Arukh – 183:1

סִימָן קפג – הִלְכוֹת נִזְקֵי מָמוֹן

183: Laws of Fiscal Damages

א: אָסוּר לְהַזִּיק מָמוֹן חֲבֵרוֹ, אֲפִלּוּ עַל דַּעַת לְֹשַלֵּם, כְּמוֹ שֶׁאָסוּר לִגְנֹב וְלִגְזֹל עַל דַּעַת לְשַׁלֵּם. וַאֲפִלּוּ לִגְרֹם נֶזֶק לַחֲבֵרוֹ, בֵּין בְּמַעֲשֶׂה בֵּין בְּדִבּוּר, אָסוּר, כְּגוֹן רְאוּבֵן שֶׁמּוֹכֵר סְחוֹרָה לַגּוֹי, וּבָא שִׁמְעוֹן וְאוֹמֵר לוֹ, שֶׁאֵינָהּ שָׁוָה כָּל כָּךְ אַף-עַל-פִּי שֶׁהָאֱמֶת כֵּן, אָסוּר, שֶׁהֲרֵי אוֹנָאָתוֹ מֻתֶּרֶת. וְכָל הַגּוֹרֵם נֶזֶק לַחַבֵרוֹ, אֲפִלּוּ בְּעִנְיָן שֶׁפָּטוּר מִדִּינֵי אָדָם, חַיָב בְּדִינֵי שָׁמַיִם, עַד שֶׁיְפַיֵס אֶת חֲבֵרוֹ

It is prohibited to cause financial damage to his friend, even with the intent to repay, just as it is prohibited to rob or to steal with intent to repay. Even causing damage to his friend, whether by act or by speech, is prohibited. For example: Re’uvein who sells merchandise to a non-Jew. Comes Shim’on and says to him [the non-Jew] that it is not worth so much — even though it is true, it is prohibited, for this overpayment is permitted. [Unlike closing a deal in which a Jew willingly overpays, which is not.] Whomever causes damages to his friend, even in a matter which is not punishable by human law, he is obligated by the law of [the One in] heave, until he appeases his friend.

In the the Qitzur’s example, the Jew’s actions qualify Re’uvein as what the Rambam would call “naval bireshus haTorah — disgusting with the permission of the Torah.” The deal is morally wrong, but not so much so as to be the subject of a Torah prohibition which would apply to all people at all times. Therefore, undermining the deal would be fiscal damages, even though the deal is not, deep down, even in Re’uvein’s spiritual best interest. The correct response would be to get the Jew not to take advantage of the non-Jew’s ignorance or naivite. Not to work against him.

Qitzur Shulchan Arukh – 182:15-16

טו: הַמּוֹצֵא פֵרוֹת בַּדֶּרֶךְ תַּחַת אִילָן שֶׁהוּא נוֹטֶה עַל הַדֶּרֶך, אִם הֵם פֵּרוֹת שֶׁדַּרְכָּן לִפּוֹל מִן הָאִילָן וּבִנְפִילָתָם הֵם נִמְאָסִים, אוֹ אֲפִלּוּ אֵינָם נִמְאָסִים אֶלָּא שֶׁרֹב הָעוֹבְרִים שָׁמָּה הֵמָּה גוֹיִם, אוֹ שֶׁהֵם פֵּרוֹת שֶׁדֶּרֶךְ הַבְּהֵמוֹת לֶאֱכֹל אוֹתָם, וְהֵן עוֹבְרוֹת דֶרֶךְ שָם, הֲרֵי הַבְּעָלִים כְּבָר נִתְיָאֲשׁוּ מֵהֶם וּמֻתָּרִים. אֲבָל אִם הֵם פֵּרוֹת שֶׁאֵינָם נִמְאָסִים בִּנְפִילָתָם, וְרֹב הָעוֹבְרִים שָׁמָּה הֵמָּה יִשְׂרְאֵלִים, אֲסוּרִים מִֹשוּם גָּזֵל. וְאִם הֵם שֶׁל יְתוֹמִים קְטַנִּים, אֲסוּרִים בְּכָל עִנְיָן, כִּי הַקְּטַנִּים, אֵין הַיֵאוּשׁ וְהַמְּחִילָה שֶׁלָּהֶם כְּלוּם

Someone who finds fruit on the path under a tree that is planted along the path, if the fruit is of the sort that normally falls from the tree and when they fall they become disgusting, or even if not disgusting, but most of those who pass there are non-Jews, or they are fruit that it is normal for animals to eat and they [often] travel this path, then the owners already gave up on them and they are permitted.

However, if they are fruit that do not become disgusting when they fall, and most of those who pass there are Jews, they are prohibited because of theft.

If they belong to young orphans, they are prohibited in every way, since the giving up on [something] or their forgiving has no [halachic import; being minors, their intent doesn't have legal weight].

טז: דִּינָא דְּמַלְכוּתָא דִּינָא

The law of the kingdom [ie the civil authorities of your country] is law.

Dina demalkhusa dina is a complicated topic, with long discussion by many rishonim as to its full scope. It is enigmatic that R’ Shelomo Ganzfried just quotes the idiom, rather than spelling out its details — it would could easily take an entire se’if (chapter)!

From its placement, we can deduce that the QSA considers dina demalkhusa to be primarily related to fiscal law and theft. But I can’t tell if he’s referring to stealing from the government, i.e. limiting the concept to taxation. Or if he is saying that property can be set by the customs defined by civil law and thus something someone else legally owns by local law may not be taken or used even if they wouldn’t have otherwise owned it according to halakhah.

Qitzur Shulchan Arukh – 182:14

יד: וּמִכָּל מָקוֹם מֻתָּר לְבֶן-בֵּיתוֹ שֶׁל אָדָם לִתֵּן פְּרוּסָה לְעָנִי אוֹ לִבְנוֹ שֶׁל אוֹהֲבוֹ שֶׁל בַּעַל-הַבַּיִת שֶׁלֹּא מִדַּעְתּוֹ, לְפִי שֶׁכָּךְ נָהֲגוּ בַּעֲלֵי הַבָּתִּים. וְאֵין זֶה נִקְרָא שֶׁלֹּא מִדַּעַת הַבְּעָלִים, כֵּיוָן שֶׁכָּךְ נָהֲגוּ, וְהַבְּעָלִים יוֹדְעִין מִזֶּה הַמִּנְהָג. וּמִטַּעַם זֶה, מֻתָּר לְקַבֵּל צְדָקָה מִן הַנָּשִׁים דָּבָר מֻעָט שֶׁלֹּא מִדַּעַת הַבְּעָלִים, הוֹאִיל וְדַרְכָּן בְּכָךְ, וְיוֹדְעִין הַבְּעָלִים שֶׁדַּרְכָּן בְּכָךְ. וְכֵן בְּפַרְדֵּס, אִם הוּא רָגִיל בּוֹ לֶאֱכֹל מִפֵּרוֹתָיו מִדַּעַת הַבְּעָלִים, מֻתָּר. וְכֵן כָּל כַּיוֹצֵא בָזֶה

But in any case, it is permitted for a member of someone’s household to give a slice [of food] to a poor person, or to the son of one of the homeowner’s beloved [friends or relation] without his knowledge because that is the custom of homeowners. It is not called “without the owners’ knowledge” since that is the custom and the owners know of this custom. For this reason, it is permissible to receive charity from women, a small thing, without knowledge of the owners [ie their husbands, assuming they didn't agree to communal property], since this is their usual way, and the owner knows that this is their way. Similarly in an orchard, if it is usual for him to eat from its fruits on the general knowledge of the owners [without this specific incidence discussed] it is permitted. Similarly anything like this.

Related to this halakhah of being able to assume the owner agrees to customary practice, R’ Daniel Eidensohn pointed me to an answer to a question I asked about 182:12:

This situation comes up in shul pretty often. There aren’t that many different styles of men coat, and it sometimes happens that someone looks through the coat room and realizes that the only remaining coat was one similar to theirs. Someone who left already took with the wrong coat.

I hadn’t heard, though, of a rabbi telling the person stuck in this situation that he is not permitted to wear the accidentally exchanged coat home.

Rav Moshe Feinstein (Igeros Moshe vol VII, Orach Chaim vol V, #9, sec 7, pg 15) opens by saying that use of the other person’s coas is prohibited. He cites Bava Metzi’ah 46a and Shulchan Arukh, Ch”M 136:3.

Then the Igeros Moshe cites the Arukh haShulchan (end of 136; hereafter AhS). The AhS rules that since wearing
the other person’s galoshes or coat is the customary response, one can assume that the owner implicitly gave permission.

Rav Moshe then sets limits. Like the fact that if the baal were to demand repayment for the value of coat rental, you would be obligated to pay it. (I wonder if that’s on Shabbos too, since that would imply a he leased you his coat on Shabbos.)

And Rav Moshe notes that since we only see this in the AhS means there must be communities where this is not the minhag. And therefore shuls that have this practice should announce it (and put up a sign, say so in the stickers in the front of shul siddurim, and things of that sort…)

Qitzur Shulchan Arukh – 182:13

יג:אָסוּר לֵהָנוֹת מִשׁוּם דָּבָר ֹשֶל חֲבֵרוֹ שֶׁלֹּא מִדַּעְתּוֹ. אַף-עַל-פִּי שֶׁבָּרוּר לוֹ שֶׁכְּשֶיִוָּדַע לִבְעָלָיו יִשְׂמְחוּ וְיָגִילוּ מִפְנֵי אַהֲבָתָם אוֹתוֹ. מִכָּל מָקוֹם אָסוּר. לְפִיכָךְ הַנִּכְנָס לְפַרְדֵּס אוֹ לְגִנַּת חֲבֵרוֹ, אָסוּר לוֹ לִלְקֹט פֵּרוֹת שֶׁלֹּא מִדַּעַת הַבְּעָלִים. אַף-עַל-פִּי שֶׁבַּעַל הַפַּרְדֵּס וּבַעַל הַגִּנָּה אוֹהֲבוֹ וְרֵעוֹ אֲשֶׁר כְּנַפְשוֹ, וּבְוַדַּאי יִשְׂמַח וְיָגִיל כְּשֶׁיִוָּדַע לוֹ ֹשֶנֶּהֱנָה זֶה מִפֵּרוֹתָיו, מִכָּל מָקוֹם כֵּיוָן שֶׁעַכְשָו אֵינוֹ יוֹדֵעַ מִזֶה, הֲרֵי הוּא נֶהֱנֶה בְּאִסּוּר. וְצָרִיךְ לְהַזְהִיר לָרַבִּים, שֶׁנִּכְשָׁלִין בָּזֶה מֵחֲמַת חֶסְרוֹן יְדִיעָה

It is prohited to get benefit from anything of a friend’s without his knowledge. Even if it is certain to him that when the owners would be informed, they would be happy and rejoice because of their love for him. In any case, it is prohibited.

Therefore, someone who enters his friend’s orchard or garden, he is not allowed to pick fruit without the knowledge of the owners. Even if the owner of the orchard and the owner of the garden love him and is his friend [as close] as his own soul, and would certainly be happy and rejoice when he is informed that this one benefited from his fruit, in any case since now he does not know about this, he is getting benefit in a prohibited manner.

We must warn the masses about this, who stumble in this because of lack of knowledge.

Qitzur Shulchan Arukh – 182:12

יב: מִי שֶׁנִּתְחַלְפוּ לוֹ כֵּלָיו בְּבֵית הַמִּשְׁתֶּה וְכַדּוֹמֶה, הַרֵי זֶה לֹא יִשְׁתַּמֵּשׁ בְּכֵלִים אֵלוּ שֶׁבָּאוּ לְיָדוֹ וְאֵינָם שֶׁלּוֹ. וִּכְשֶׁיָבוֹא בַּעַל הַחֵפֶץ, צָרִיךְ לְהַחֲזִירוֹ לוֹ, וְאַף-עַל-פִּי שֶׁהַחֵפֶץ שֶׁלּוֹ נֶאֱבָד. וְכֵן כּוֹבֶסֶת הַמְכַבֶּסֶת לְרַבִּים וְהֵבִיאָה לוֹ חָלוּק שֶׁאֵינוֹ שֶׁלּוֹ, אָסוּר לְלָבְשוֹ, אֶלָּא צָרִיךְ לְהַחֲזִירוֹ לִבְעָלָיו, וְאַף-עַל-פִּי שֶׁשֶּׁלּוֹ נֶאֱבָד. אַךְ אִם מֻנָּח אֶצְלוֹ יָמִים רַבִּים, עַד שֶׁאִי אֶפְשָׁר שֶׁלֹּא חָקְרוּ הַבְּעָלִים בֵּינְתַיִם אַחַר שֶׁלָּהֶם, אָז מֻתָּר לוֹ לְלָבְשוֹ, כִּי מִסְּתָמָא סִלְּקָה הַכּוֹבֶסֶת אֶת בְּעָלָיו וְשִׁלְּמָה בְּעַד הֶחָלוּק הַזֶה

Someone whose utensils were switched in the pub or the like, he should not use the utensils that came to his hand that weren’t his. When the owner of the item comes, he must return it — even if his own item is lost. Similarly a washer-woman who washes [clothes] for the community and brings him a shirt which is not his, it is prohibited to wear it. Rather, he must return it to its owners — even if his own was lost.

However, if it rests with him many days, until it is impossible that the owners didn’t search in the meantime for their own, then it is permitted for him to wear it. Because by default [you may assume that] the washer-woman cleared [the matter] with its owners and paid for this shirt.

This situation comes up in shul pretty often. There aren’t that many different styles of men coat, and it sometimes happens that someone looks through the coat room and realizes that the only remaining coat was one similar to theirs. Someone who left already took with the wrong coat.

I hadn’t heard, though, of a rabbi telling the person stuck in this situation that he is not permitted to wear the accidentally exchanged coat home.

Qitzur Shulchan Arukh – 182:10-11

י: וְלָכֵן מִי שֶׁהוּא גַנָּב אוֹ גַזְלָן מְפֻרְסָם, שֶׁאֵין לוֹ מְלָאכָה אַחֶרֶת אֶלָּא זֹאת, וְכָל מְמוֹנוֹ בְּחֶזְקַת גָנוּב אוֹ גָזוּל, אָסוּר לֵהָנוֹת מִמֶּנוּ, וְאָסוּר לְעָנִי לָקַחַת מִמֶּנּוּ צְדָקָה

[Continuing the topic of buying or getting benefit from stolen merchandise...] Therefore, anyone who is a known robber or thief, who has no job other than this, and [therefore] all his money is presumed to be robbed or stolen, it is prohibited to get any benefit from him, and a poor person may not take charity from him.

יא: וְכֵן אִם אֶחָד רוצֶה לִמְכֹּר אֵיזֶה חֵפֶץ שֶׁנִּרְאֶה שֶׁהוּא גָנוּב, כְּגוֹן שׁוֹמְרֵי פֵּרוֹת שֶׁמּוֹכְרִים פֵּרוֹת בְּמָקוֹם צָנוּעַ, אוֹ מוֹכֵר אַחֵר שֶׁנּוֹשֵׂא אֵיזֶה דָבָר בְּהַצְנֵעַ לְמָכְרוֹ, אוֹ שֶׁאוֹמֵר לְהַקּוֹנֶה, הַטְמֵן, אָסוּר לִקְנוֹת. וַאֲפִלּוּ לִקְנוֹת מֵאִשָּׁה אֵיזֶה דָבָר שֶׁיֵשׁ לָחוּשׁ שֶׁהִיא מוֹכֶרֶת שֶׁלֹּא מִדַּעַת בַּעְלָּה, אוֹ לִקְנוֹת מֵאִישׁ דָּבָר מִתַּכְשִׁיטֵי הָאִשָּׁה וּמַלְבּוּשֶׁיהָ, שֶׁיֵשׁ לָחוּשׁ שֶׁהוּא מוֹכְרוֹ שֶׁלֹּא מִדַּעַת אִשְׁתּוֹ, אָסוּר

Similarly, anyone who wants to sell any item that appears to be stolen, such as the guardians of fruit who are selling fruit in some hidden place, or another seller who carries an item into a hidden place to sell it, or who tells the buyer “wait [for someone to pass by]“, it is prohibited to buy. Even buying from a woman some item that there is reason to suspect she is selling it without her husband’s knowledge, or to buy from a man an item of his wife’s jewelry or clothing that there is reason to suspect that he sells it without his wife’s knowledge, is prohibited.