Rambam - 1 Chapter a Day

For in none of these cases is there another person who willingly transfers his ownership of the property (Maggid Mishneh).

See Hilchot Mechirah 1:8-16.

lbid.:16. Note the comments of the Ra’avad (both in that source and here), which state that eating produce is not considered to be an effective means of manifesting ownership.

It can be explained that this refers to the chazakah, proof of a claim of continued ownership for three years during which one benefitted from the property, as explained in Hilchot To’en V’Nit’an 11:2. This is effective with regard to a claim that one purchased the property from another person, for had he seen the person benefitting from his land, he would have protested. With regard to the property of a deceased convert, however, this is not relevant, for since the convert has died, there is no one to protest, and the acquisition of such land is brought about not by benefitting from it, but by making an improvement in the land itself.

In each context, the concept of chazakah, manifesting ownership, has a different meaning, and different laws therefore result. It would appear that the chazakah referred to within the context of proving a claim of ownership refers to activities that would be performed only in a person’s own home. The chazakah referred to with regard to acquisition of the property of a deceased convert, by contrast, refers to any change within the property that provides a person with benefit (Kin’at Eliyahu).

The intent is that he made an ornamental pattern in the plaster.

The Maggid Mishneh states that it is significant that the painting or the plaster work is done opposite the entrance. Therefore, it is noticeable despite the fact that it is small. If it is done in another portion of the house, a larger area must be painted or plastered.

See the for and the Ramah (Choshen. Mishpat 275:15), who state that the person must also lie down on the mattresses to benefit from the land itself (in contrast to eating produce). Alternatively, according to the Shulchan. Aruch (ibid.), this refers to an instance where in order to lay down the mattresses, the person had to level the land and thus improve it

This ruling aroused the attention of the commentaries. For the Rambam rules in Hilchot Mechirah 1:16 that a person who plows a field that he purchased with the intent of leaving it fallow acquires it. If so, why does the Rambam give leaving a field fallow as an example of the principle: “There are many acts that if [performed] by a purchaser to prove ownership [of property are] not [effective], but when performed to manifest ownership over ownerless property, property belonging to a [deceased] convert or the like, are effective in acquiring it”?
The difficulty was brought to the attention of Rabbenu Yehoshua, the Rambam’s grandson. He explains that leaving a field fallow for three years is not an effective kinyan, as reflected by the fact that it is not sufficient to substantiate a claim of continued ownership as stated in Hilchot To’en V’Nit’an 12:9. Hence, were the laws pertaining to the acquisition of the property of a deceased convert not more lenient, it would not be effective with regard to the acquisition of such property.
Why is it effective in the presence of the owners, as stated in Hilchot Mee hi rah 1:16? Because a person would never plow a field belonging to someone else in that person’s presence. Hence, it is evidence that a change of ownership took place.

For this is comparable to eating produce, which, as explained in Halachah 2, is not sufficient to acquire the property of a deceased convert.

I.e., how can we determine his intent?

The Tur and the Ramah (Choshen Mishpat 275:18) state that even if the person claims to be performing the activity to improve the land, his claim is not accepted, because his actions indicate the opposite.
See Hilchot Sh’vitat Yom Tov 8:12, which mentions the circumstances described in this and the following halachot.

For the small branches are not valuable for firewood, while the large branches are.

For he is seeking to bring the entire land to a uniform level.

For the water will remain within the field and irrigate it.

The Ramah (Choshen Mishpat 275:21) states that even if the first person set up the doors, if he did not close them and the second person does close them, the second person acquires the property.

The Maggid Mishneh cites the commentary of the Rambam’s teacher, the Ri Migash, on Bava Batra 53b, which states that not only does the second person acquire the property of the deceased convert, he also acquires the building constructed by the first person. For placing his building materials on land that is ownerless is equivalent to declaring the materials ownerless.
The Ramah (op. cit.) quotes this opinion, but also quotes an opinion that states that if a person constructed the building with his own building materials, neither he nor the second person acquires the property.

In this instance as well, the Maggid Mishneh quotes the commentary of the Ri Migash, which states that if the person dug into the earth to build foundations for the building, he acquires the property. There appears to be an allusion to this concept in the Rambam’s wording, “the first person did not do anything with the land itself.” This opinion is also cited by the Ramah (op. cit.). The Ramah, however, also quotes the opinion of Rabbenu Asher, that digging the foundations of the building is not sufficient to acquire it.

From this phrase, the Maggid Mishneh derives that if the construction performed by the first person was at all useful - e.g., his deeds made it possible to keep chickens or livestock within the building - he acquires it. This ruling is quoted by the Ramah (op. cit.).

If, however, he covered the seeds, he does acquire the property (Maggid Mishneh).

Significantly, when, by contrast, a person purchases a field from a colleague, he acquires it by sowing it (Hilchot Mechirah 1:16).

For the produce had not grown at that time.

And not as a result of his efforts.

Because the partition that he set up is of no benefit.

This law is derived from the laws mentioned in the following halachah (Maggid Mishneh).

E. g., the fields bordered on each other. He started plowing in his field, and without realizing it he continued plowing in the convert’s field.

For one must have both deed and intent to acquire the property.

The Maggid Mishneh states that this ruling applies regardless of whether the security was given at the time the loan was made or afterwards.

Although Bava Metzia 82a states: “A creditor acquires security [given him],” this means that he must take responsibility for the security if it is destroyed. (See Hilchot Sechirut 10:1.) The security is, however, considered to belong to the debtor, for he has the right to redeem it at any time. Note, however, the comments of the Siftei Cohen 72:149.

I.e., before the creditor does. Note also the following halachah.

For the creditor’s lien on the security is not nullified by the convert’s death. The Maggid Mishneh extends this principle further and states that if a creditor has a promissory note or witnesses who will testify that the convert owes him money, a lien is established on the convert’s property, and it is is not nullified by his death. This applies even if the convert does not own any landed property.

For he took possession of it.

See Hilchot Gezelah Va’Avedah 17:8, which states that when a courtyard is protected, any ownerless article that falls into the courtyard is acquired by the owner. If the courtyard is not protected, the owner must stand next to his courtyard and express his desire that his courtyard acquire on his behalf. Similarly, in the present instance, the security belonging to the convert becomes ownerless upon his death. Since it is located in the creditor’s property, he acquires it immediately.

For it has already become the property of the creditor.

For immediately upon the convert’s death, they manifest ownership over themselves. This occurs automatically even without their conscious decision. They do not even require a bill of release (Beit Yosef, Yoreh De’ah 267). Thus, they become free before they can be acquired by anyone else.

For they do not possess an independent financial capacity with which they can acquire their freedom. (See Tosafot, Gittin 39a.)

See Hilchot Mechirah 2:1-4.

In these instances, the property remains in the convert’s possession or in his estate, to be inherited by his child (or child to be born).

Without leaving any heirs, in which instance the convert does not have any heirs.

For they gave up their possession when they heard the second rumor (Sefer Me’irat Einayim 275:41).