Bava Metzia, Chapter 2, Mishnah 3. In the previous mishnah, two possibilities were established for one who finds a lost object: either he is permitted to keep the find for himself, or he is obligated to announce it to fulfill the mitzvah of returning a lost object, and wait for the owner to come and provide an identifying mark. The Mishnah's approach throughout the entire chapter is not, "I found an object, am I allowed to keep it?", but rather, "I found an object, what is my obligation toward my fellow Jew who is the owner?" The first mishnah taught that if the owner despaired, since he will never get the object back, the obligations no longer apply, and the finder is permitted to keep the find. The second mishnah discusses an object that the owner presumably has not despaired of, and therefore the finder is obligated to do his utmost to return it.
There is a third possibility, which is neither of these: the finder is not permitted to keep the object for himself, yet he is also not obligated to take it and announce it. This is a situation where taking the object and announcing it would cause the true owner more trouble than if the object were left in its place. The starting point of our mishnah is, therefore, a new question: where was the lost object found? Aside from the questions asked previously - whether the object has an identifying mark or not, whether it was placed down intentionally or fell accidentally - the Mishnah wishes to clarify in what type of place the object was found.
Three types of locations:
Makom hamishtamer - a protected area, a safe place to leave an object and return to take it later.
Makom she'eino mishtamer - a completely unprotected place, where an object placed there will no longer be found, due to scavengers and the like.
Makom hamishtamer ketzat - an intermediate category, a partially protected place that is somewhat safe but not entirely. When an object is found in such a place, the question remains in doubt: did the owner place it there intentionally with the intent to return and take it, or did he leave it there by mistake? From this doubt stems the question of whether the mitzvah of returning a lost object applies here, or if the object should be left in its place.
"Matza achar hagapah o achar hagader gozalot mekusharim":
The 'gapah' is a type of fence, and the 'gader' in the Mishnah is not like a fence in our modern language, but rather a low wall made of stones piled on top of one another, which functions as a fence. Behind this fence, tied fledglings were found - young birds whose wings were tied, and because of this they cannot fly away from there. However, since these are merely fledglings, they do not have an identifying mark: the manner of tying the wings backward or downward is the standard way, and there is nothing unique about it. Consequently, the one who lost them cannot provide an identifying mark to claim them back, and furthermore, these animals move from place to place and do not have a fixed location.
The same applies if the fledglings were found "bishvilin shebasadot" - on paths in the fields, a side path between the hills, somewhere in the fields, where the public does not typically pass, and therefore it too falls under the category of a partially protected place where objects can be left for a short time. Now we are in doubt: did a person place the fledglings there intentionally with the intent to return and take them, or were they perhaps lost from him and he wishes to get them back? And even if they were lost from him, what benefit is there in taking them? What identifying mark could he provide? There is no certainty in the number of fledglings, there are no identifying marks, since there is nothing unique about them, and there is no exact location where they were placed, as the fledglings hop from their place. Therefore, the Mishnah states: "Harei zeh lo yiga bahen" - he should not touch them. He should not take them, because by taking them the finder harms the owner who is likely to return and has not yet despaired, and it is very possible that the object belongs to someone else. And since it is a rabbinic doubt, he should not take them, but rather leave them in their place.
"Matza kli be'ashpah":
In the world of the Mishnah, people did not throw away objects; rather, if there was any use in them, however small, they would reuse them. Unlike in our days, when if a knife is found in the garbage with a loose handle, or a chipped mug, it is clear that they are nothing but trash - in the Mishnah, the assumption is that a person wants his knife or his mug even if they are loose or chipped, and therefore the finder must assume that the owner wants it back. Furthermore: the garbage dump is not merely a place for disposal, but also a place for hiding things. In the past, there was not much storage space, and when a person possessed a valuable object and had nowhere to put it, he would hide it in a place where people were not frequently found, such as the garbage dump, in order to return and take it later. This refers to a permanent garbage dump that is not cleared away periodically, so the object will remain there until the owner comes to claim it.
The Mishnah says: "Im mechuseh" - if the found object was completely hidden and buried, for example, if a person dug a hole in the garbage dump, placed his cup in it and covered it again, and when the finder dug in the garbage dump to find a place to hide his own cup he stumbled upon his friend's cup - he must assume that his friend preceded him and placed it there for safekeeping, with the intention of returning to take it. Therefore, "lo yiga bo" - he should not touch it, but rather leave it in its place, for it is clear that it was placed there intentionally, and this is not a lost object at all that involves a mitzvah, but rather a person's safe hiding place. And even if the finder wishes to be stringent out of doubt, to take it and announce it so that the owner can get the object back - the Rambam writes that by doing so he burdens the owner: the owner will come to look for his object when he needs it, will not find it in its place, and will be forced to track down the finder, which is a great hassle. Therefore, it is better not to do anything, since the evidence, as the Mishnah sees it, indicates that the object was placed there intentionally and is not a lost object.
But "im meguleh" - if the object was found in the garbage exposed, it indicates that it was not hidden there and was not placed there intentionally. And even though it is a garbage dump, the Mishnah assumes that for an item fit for wearing or for use, there is no logic to say it was discarded; rather, they will wear it with a patch or use it even if it is damaged. For this reason, "notel umachriz" - he takes it and announces it to return it to its owner. The assumption is that every item has some identifying mark, and that the owner wants it.
"Matza begal uvechotel yashan":
Sometimes an object is found in a protected place, but it is so old that one can safely assume the owners have already despaired of it long ago, or that it never belonged to a Jew. For the verse says, "to your brother" - your brother is the one to whom you must return a lost object, and this does not apply to a non-Jew. A "gal" is a mound or heap: a wall that crumbled and became a pile of rubble, and inside the pile of stones, for example, a knife was found. The same applies if the knife was found inside an old wall.
What is an old wall? A wall that has stood for so long that it has been forgotten who built it and its origin is unknown to us. Because of this, it is highly likely that a previous owner, a non-Jew who lived here in the past or any other person, hid the knife in the wall, and in the meantime the wall fell and became old, indicating that the object belongs to someone else. The reason for this, as the Gemara explains, is that this involves an object that looks as though it has been there for a very long time: even if it has an identifying mark, it has gathered rust in the meantime and is completely covered in it. It is therefore clear that whoever left it here forgot about it long ago and abandoned it, making it ownerless property, and therefore the finder is permitted to take it.
However, if the object is found in a "new" wall, this does not mean a wall built last week; it could have been standing there for a hundred years. Rather, it means that if the person living there today has resided in the place since his great-grandfather built the wall, and his grandfather inherited the house from his great-grandfather, and he inherited it from his grandfather - then the identity of the owners is known to us, and we know that what is found in the wall belongs to them. We must assume, therefore, that the object belongs to the owner of the house and the property. Someone who rents the place for a weekend as a guest is not permitted to assume that the object is his; we must assume it belongs to the owner of the property, since it was there from the beginning, just as the wall stood there from the beginning.
The Mishnah continues and clarifies: if there is a hole in the wall going straight through from one end to the other, with one end facing the private domain and the other end facing the public domain - it is possible that the resident there, or his grandfather, thrust the object into the wall and forgot about it, and it is still theirs; and it is possible that a person from the street placed it there for safekeeping, intending to return and take it, but forgot. Therefore, when a rust-covered object is found that has been there for a long time, its location within the wall is what will determine where it came from.
In the outer half of the wall - the side facing the public domain and closest to it: if the object is covered in rust or dust, or is rotten if it is made of wood, it is a sign that it was left there a long time ago, and whoever left it there will certainly not return, for he would not have let his object rot. And since it is on the side facing the public domain, a person from the street presumably left it there. Therefore, "shelo" - the finder is permitted to keep it, even if it has an identifying mark, since it was abandoned, and one can safely assume that the owner will not come looking for it, but rather lost hope and despaired, making it ownerless property, and the finder acquires it.
In the inner half of the wall - the side closer to the house's property than to the public domain: the finder is not permitted to take the object, and he is obligated to return it to its owner. Even if it is clear that the object has been lying there for about fifty years, as long as it is a "new" wall, meaning that it belonged from the beginning of its construction to the family that owns the building today - the object is still theirs. And even if the grandfather forgot about it, this does not make it ownerless; it is in their domain and remains theirs forever.
The Gemara notes that the ruling based on the side closest to the private or public domain applies to an object that is held from both its sides, such as a spoon. But with a sharp knife, where a person does not hold the blade but rather its handle, one can see which direction it is facing and from where it was inserted, since it was inserted from the direction of the handle. Therefore, it belongs to the place the handle faces: if the handle faces toward the public domain, it belongs to the public domain, and vice versa.
"Im hayah maskir la'acherim" - If he had rented it out to others:
The final case deals with a house that was rented to many tenants. The language of the Mishnah is cryptic: "Im hayah maskir la'acherim, afilu betoch habayit, harei elu shelo" - if he had rented it out to others, even inside the house, they are his. In other words, even if the object is found inside the house, and even if it has an identifying mark, the finder is permitted to take it. And why? The Gemara says that it is impossible to understand the Mishnah simply, for it contradicts everything stated throughout the entire chapter. The foundation of the matter is that when several people lived in a place, each of them took his belongings with him upon leaving, checked for them, and left nothing behind; therefore, anything found in the place can be safely assumed to belong to the last tenant who lived there. The Gemara establishes our Mishnah in one of two ways:
That the previous tenant was a non-Jew - and because of this, the mitzvah of returning a lost object does not necessarily apply, and the finder is permitted to keep the object for himself.
That the previous tenants were three people unrelated to each other, and all of them were Jews - and since the object could belong to any of the three, the one who lost it will assume that one of the other two stole it from him, and therefore he certainly despaired. And when this is the reasonable assumption, the finder is permitted to keep the object for himself, since he can safely assume that the loser will not return to take it because he has despaired.
It is worth noting that even though the mitzvah of returning a lost object does not apply toward a non-Jew, as it says "your brother" - your fellow Jew - there are many cases where the right thing to do is to return the lost object to a non-Jew, for the sake of Kiddush Hashem and for the sake of the ways of peace. It goes without saying that great enmity will be created if a person knows that his belongings were found and are not being returned to him. In practice, therefore, it is not so simple, even though the mitzvah of returning a lost object in itself certainly does not apply - neither as a positive commandment nor as a negative commandment - toward a non-Jew.
In conclusion: In this Mishnah, a new question was added to clarify the law of finding a lost object - in what type of place was the lost object found: a protected place, an unprotected place, or a somewhat protected place. We learned that with tied young birds found behind a fence or in pathways in the fields, which have no identifying mark and their location is not fixed, "lo yiga bahen" - one should not touch them; with a vessel found in a garbage dump - if it is covered, it is a hiding place and he should not touch it, and if it is uncovered, he takes it and announces it; in a gal and an old wall, where the object has been sitting for a long time and its origin is unknown, it is his, while in a new wall whose owners are known - its outer half is his and its inner half belongs to the homeowner, and with a knife we follow the direction of the handle; and in a house that was rented out to others - they are his, whether the previous tenant was a non-Jew or whether three Jews unrelated to each other lived in it, for the one who lost it certainly despaired.
Since these halachos are somewhat complex, regarding practical halachah it is proper to consult a Rav who is a posek.