The Gemara answers: The practical difference is with regard to returning the bill of divorce of a woman that was lost by an agent before its delivery, on the basis of distinguishing marks. If you say that the identification of an item on the basis of distinguishing marks is by Torah law, we return the document and allow the agent to transmit it to the woman. But if you say that it is by rabbinic law, we do not return the document, because when the Sages institute an ordinance, it is only with regard to monetary matters they have the authority to declare property ownerless; but with regard to ritual matters, the Sages do not institute an ordinance. They lack the authority to abrogate the prohibitions by Torah law that are associated with a woman’s marital status.

The Gemara suggests: Come and hear proof from the mishna: The garment was also included in the generalization that one must return all of these items. And why did it emerge from the generalization that is should be specified? To draw an analogy to it and to say to you: What is notable about a garment? It is notable in that there are distinguishing marks concerning it and it has claimants asserting ownership, and its finder is obligated to proclaim his find. So too with regard to any item concerning which there are distinguishing marks and it has claimants asserting ownership, its finder is obligated to proclaim his find. Clearly, the identification of an item on the basis of distinguishing marks is by Torah law. The Gemara rejects the proof: Perhaps it was necessary for the tanna to mention only the criterion of claimants, and the tanna cited the criterion of distinguishing marks for no reason, as by Torah law distinguishing marks are not a relevant factor.

The Gemara suggests: Come and hear proof from the aforementioned statement: The obligation to return a donkey to its owner on the basis of the distinguishing marks of the saddle is derived based on the mention of the word “donkey” in the verse from Deuteronomy. Clearly, the identification of an item on the basis of distinguishing marks is by Torah law. The Gemara rejects this proof: Emend the baraita and say: There is an obligation to return the donkey only on the basis of witnesses who testify with regard to the identity of the owner based on the fact that the saddle belongs to him, and not on the basis of distinguishing marks.

The Gemara suggests: Come and hear proof from a mishna (28b): “And if your brother be not near you, and you know him not, then you shall bring it into your house, and it shall be with you until your brother claims [derosh] it, and you shall return it to him” (Deuteronomy 22:2). Would it enter your mind that he would give the lost item to him before he claims it? How can the finder return it if he does not know the identity of the owner? Rather, the verb derosh is not referring to the claim of the owner; it is referring to the scrutiny performed by the finder. Scrutinize him [darshehu] to determine whether the claimant is a swindler or whether he is not a swindler. Only then may you return the lost item to him.

The Gemara states its suggested proof: What, is it not that the one who claims the lost item proves that he is not a swindler on the basis of distinguishing marks that he provides? Apparently, the identification of an item on the basis of distinguishing marks is by Torah law. The Gemara rejects this proof: No, the determination of whether he is a swindler is on the basis of scrutinizing his witnesses.

The Gemara suggests: Come and hear proof from a mishna (Yevamot 120a): One testifies that a man died, thereby permitting his wife to remarry, only if he can testify about seeing the countenance [partzuf ] of the face with the nose, as this allows one to identify the individual with certainty. Although there are distinguishing marks on his body and on his garments, which appear to indicate his identity, they cannot be used to identify the person.

The Gemara states its suggested proof: Conclude from it that the identification of an item on the basis of distinguishing marks is not by Torah law. The Sages say in rejecting that proof: The distinguishing marks on his body mentioned in the mishna are non-specific distinguishing marks, e.g., that he was tall or short, and that is the reason that the distinguishing marks are ineffective in determining his identity. The distinguishing marks on his garments mentioned in the mishna are ineffective in determining his identity, as we are concerned about the possibility of a loan, e.g., perhaps the husband loaned his clothes to the deceased.

The Gemara asks: If we are concerned about the possibility of a loan, how do we return a donkey to its owner on the basis of the distinguishing marks of the saddle; perhaps it was borrowed? The Sages say in response: People do not typically borrow a saddle because saddles that are not custom fit wound the donkey.

If you wish, say instead: The distinguishing marks on his garments mentioned in the mishna are non-specific distinguishing marks, e.g., where the witness said that they were white or red, and that is the reason that the distinguishing marks are ineffective in determining his identity.

The Gemara questions the previous answer with regard to the concern about the possibility of a loan. But there is that which is taught in a baraita: If the agent found the bill of divorce that he lost bound to his pouch, or his purse, or his signet ring, or if he found it among his garments, even if he found it a long time after he lost it, the distinguishing marks on those items are sufficient in order to identify the bill of divorce as the one that he lost, and it is valid. And if it enters your mind that we are concerned about the possibility of a loan, when he found the bill of divorce bound to his pouch, why is it valid? Let us be concerned about the possibility of a loan and that perhaps the pouch and the bill of divorce belong to someone else.

The Sages say in response: There is no concern in this case, as people do not loan a pouch, a purse, or a signet ring to another person. One does not loan his pouch and his purse to others due to the fact that it portends the loss of his good fortune. And one does not loan his signet ring to others due to the fact that it could be used to forge documents.

The Gemara suggests: Let us say that the dilemma whether the identification of an item on the basis of distinguishing marks is by Torah law or by rabbinic law is the subject of a dispute between tanna’im, as it is taught in a baraita: One does not testify on the basis of a mole on the body of the deceased to determine the identity of a man who died and permit his wife to remarry. And Elazar ben Mahavai says: One testifies to identify the corpse on the basis of a mole. What, is it not with regard to this matter that they disagree; as the first tanna holds that identification of an item on the basis of distinguishing marks is by rabbinic law and therefore, testimony concerning those marks cannot dissolve a marriage by Torah law; and Elazar ben Mahavai holds that identification of an item on the basis of distinguishing marks is by Torah law.

Rava said: That is not necessarily the crux of their dispute, as perhaps everyone agrees that identification of an item on the basis of distinguishing marks is by Torah law, and here, it is with regard to whether one needs to be concerned that a mole is often found on one’s contemporary, i.e., one born under the same constellation, rendering it useless as a means of identification, that they disagree. One Sage, the first tanna, holds that a mole is often found on one’s contemporary and therefore it is insufficient as a means of identification; and one Sage, Elazar ben Mahavai, holds that a mole is not often found on one’s contemporary, and therefore it is sufficient as a means of identification.

If you wish, say instead that everyone agrees that a mole is not often found on one’s contemporary, and here it is with regard to whether the appearance of distinguishing marks on the body is apt to change after death that they disagree. One Sage, the first tanna, holds that the appearance of distinguishing marks is apt to change after death, and that consequently they are insufficient as a means of identification; and one Sage, Elazar ben Mahavai, holds that the appearance of distinguishing marks is not apt to change after death, and therefore, they are sufficient as a means of identification.

If you wish, say instead that everyone agrees that a mole is not apt to change after death, and that the identification of an item on the basis of distinguishing marks is by rabbinic law, and here it is with regard to whether a mole is a clear-cut distinguishing mark that they disagree. One Sage, Elazar ben Mahavai, holds that a mole is a clear-cut distinguishing mark that can be relied upon without hesitation even in matters of Torah law, e.g., dissolving a marriage; and one Sage, the first tanna, holds that a mole is not a clear-cut distinguishing mark. Since standard distinguishing marks are sufficient by rabbinic law, a marriage, which is in effect by Torah law, cannot be dissolved on the basis of a mole.

Rava says: If you say that the identification of an item on the basis of distinguishing marks is not by Torah law, how do we return a lost item to the presumed owner on the basis of distinguishing marks; perhaps it will result in the return of property to one who was in fact not the owner? Rava answers: We return the lost item, as it is satisfactory to the finder of a lost item to return it on the basis of distinguishing marks, rather than exercise his right by Torah law to retain it, so that when an item is lost from him in the future, the finder will return it to him on the basis of distinguishing marks as well.

Rav Safra said to Rava: But can a person perform an act that results in benefit for himself with property that is not his? The lost item belongs not to the finder but to the one who lost it. How can the finder waive the right of the true owner to the lost item so that he may recover his own lost item in the future?

Rather, we return the lost item, as it is satisfactory to the owner of the lost item to be able to provide a description using distinguishing marks and on that basis take possession of the item. He knows that he has no witnesses to testify to his ownership, and he says: No one else knows the clear-cut distinguishing marks that are on the item. And I will provide a description using the clear-cut distinguishing marks, and based on that information I will take possession of the item. Each owner gives his tacit agreement to the return of lost items on the basis of distinguishing marks, based on the belief that he is best able to identify them.

The Gemara asks: But there is that which we learned in a mishna (20a), that Rabban Shimon ben Gamliel says: If one found three promissory notes relating to the loan of one debtor who borrowed money from three creditors, he must return the documents to the debtor. If one found three promissory notes relating to the loans of three debtors who borrowed money from one creditor, he must return the documents to the creditor. If one returns lost items on the basis of distinguishing marks due to the tacit agreement of the owners, is it satisfactory to the debtor to have the documents returned to the creditor, as doing so would enable the creditor to collect payment of the loan?

Rava said to Rav Safra: There, the obligation to return the promissory notes to the creditor is not on the basis of distinguishing marks; rather, it is based on logical reasoning. If one found three promissory notes relating to the loan of one debtor who borrowed money from three creditors, he shall return the documents to the debtor, because a group of several documents indicating that one debtor borrowed money from several creditors is typically found with the debtor and is not typically found with a creditor, as the only element common to all the documents is the debtor. Conclude from it that the group of documents fell from the debtor while they were in his possession. If one found three promissory notes relating to the loans of three debtors who borrowed money from one creditor, he shall return the documents to the creditor, because a group of several documents indicating that multiple debtors borrowed money from a single creditor is typically found with the creditor and is not typically found with a debtor, as the only element common to all the documents is the creditor.