1) THE DEFINITION OF "MEDINAS HA'YAM"
QUESTIONS: The Mishnah states that a Shali'ach who delivers a Get from "Medinas ha'Yam" must testify, "b'Fanai Nichtav uv'Fanai Nechtam" -- "In front of me it was written and in front of me it was signed." RASHI explains that "all of Chutz la'Aretz" is called "Medinas ha'Yam" except for Bavel (as the Gemara says later on 6a).
Why does Rashi write that all of Chutz la'Aretz is considered Medinas ha'Yam? It is clear from the continuation of the Mishnah that the Tana Kama refers only to places which are distant from Eretz Yisrael. The Tana Kama disagrees with Raban Gamliel who rules that a Shali'ach who comes from a place near Eretz Yisrael must say "b'Fanai Nichtav...." (The Tana Kama certainly disagrees with Rebbi Eliezer who rules that a Shali'ach must say "b'Fanai Nichtav" when he comes from places in Chutz la'Aretz that are adjacent to Eretz Yisrael and surrounded on three sides by the borders of Eretz Yisrael.) Why does Rashi assume that according to the Tana Kama, a Shali'ach who comes from any part of Chutz la'Aretz must say "b'Fanai Nichtav"? (RASHBA and Rishonim.)
(a) RABEINU KRESKAS (printed with the Chidushei ha'Ritva) suggests that Rashi understands that the cities of Rekem and Cheger, and the cities that are "Muvla'os," were actually included in the conquest of Yehoshua and became part of Eretz Yisrael at that time. However, when the Jews returned from the Galus in Bavel they did not resettle those cities. Since they were not resettled, they are not considered part of Eretz Yisrael with regard to the Halachah of "b'Fanai Nichtav." Nevertheless, Rashi does not include those cities in his term "Chutz la'Aretz" since they were part of the original conquest of Yehoshua. Hence, he justifiably writes that "all of Chutz la'Aretz" -- which excludes these cities -- is considered Medinas ha'Yam.
Rabeinu Kreskas himself does not accept this explanation.
(b) The PNEI YEHOSHUA suggests that according to Rashi, the Tana Kama maintains that even when a Shali'ach delivers a Get from a city near Eretz Yisrael, he must say "b'Fanai Nichtav." The Tana Kama excludes only cities that are "Muvla" within the boundaries of Eretz Yisrael. He does not call those cities "Chutz la'Aretz" since an imaginary line drawn from the farther points of the two outer borders would leave those cities within Eretz Yisrael. Therefore, when Rashi uses the words, "all of Chutz la'Aretz," he excludes those cities.
Raban Gamliel, who argues and says that one who brings a Get from Rekem must say "b'Fanai Nichtav," means that although Rekem is "Muvla" one nevertheless must say "b'Fanai Nichtav" when he brings a Get from there since it is far from the main populated areas. Rebbi Eliezer adds that even if it is "Muvla" and near the main populated areas, one still must say "b'Fanai Nichtav."
(Rashi later (4a, DH v'Amar Abaye), however, does not seem to follow this approach.)
(c) TOSFOS (DH mi'Medinas ha'Yam) asks why the Mishnah discusses bringing a Get "from Medinas ha'Yam" and not "from Chutz la'Aretz." He answers that the term "Medinas ha'Yam" implies countries that are distant from Eretz Yisrael and excludes cities that are "Muvla'os" and "Semuchos." However, as the RASHBA points out, the Gemara later (4a) seems to include even "Muvla'os" and "Semuchos" in the category of "Medinas ha'Yam." (See Rashi there, DH v'Asa.)
The RAN answers that "Medinas ha'Yam" does not mean "distant places" but places that literally are across the sea (countries in the direction of the sea). Since the sea is the western boundary of Eretz Yisrael, there are no cities that are "Muvla" (engulfed on three sides) or "Samuch" (adjacent) to Eretz Yisrael on that side. The Tana uses the words "Medinas ha'Yam" as a reference to countries to the west of Eretz Yisrael in order to exclude "Muvla'os" and "Semuchos." However, the same Halachah applies to cities in other directions from Eretz Yisrael which are not "Muvla'os" or "Semuchos."
The Ran explains that this is how Rashi translates "Medinas ha'Yam." When Rashi says that all of Chutz la'Aretz is called "Medinas ha'Yam," he does not mean all cities, regardless of how far away they are. Rather, he means the cities on all sides and not just the west side (even though "Yam" refers to the west). (See MAHARAM SHIF.)
This explains the end of Rashi's comments in which he writes that all of Chutz la'Aretz is considered Medinas ha'Yam except for Bavel, as the Gemara says later. Why does Rashi need to discuss the status of Bavel here? Moreover, the Gemara later cites a dispute about whether Bavel is like the rest of Chutz la'Aretz or not. According to this explanation, these questions are answered. Rashi proves that Medinas ha'Yam is not limited to the west of Eretz Yisrael, since the Amora'im discuss whether Bavel is included. Bavel is not to the west of Eretz Yisrael, and thus it certainly would not be included if "Medinas ha'Yam" would refer only to the west. It must be that "Medinas ha'Yam" includes all of Chutz la'Aretz, even the parts immediately adjacent to the four sides of Eretz Yisrael. Although Rashi does not address whether cities near Eretz Yisrael are called "Medinas ha'Yam," it is obvious from the context of the Mishnah that those cities are not called "Medinas ha'Yam."
2) SUMMARY: THE BOUNDARIES OF ERETZ YISRAEL
The Gemara discusses the boundaries of Eretz Yisrael. The identification of the boundaries of Eretz Yisrael involves various historical and geographical issues. The following is a synopsis of the historical aspect of the identification of the boundaries of Eretz Yisrael based on the Gemara, the Book of Maccabees, and Josephus, as prepared by Rabbi Yehudah Landy. (This discussion is not intended for use for practical Halachic purposes.)
I. THE MISHNAH'S CONTEXT: THE FIRST CONQUEST OR SECOND CONQUEST OF ERETZ YISRAEL
QUESTION: The Mishnah (2a) quotes Rebbi Yehudah who states that the borders of Eretz Yisrael are "from Rekem to the east, and Rekem is part of the east; from Ashkelon to the south, and Ashkelon is part of the south; and from Ako to the north, and Ako is part of the north."
Eretz Yisrael was sanctified twice, first by the Olei Mitzrayim, the Jews who entered the land after Yetzi'as Mitzrayim, led by Yehoshua, and a second time by the Olei Bavel, the Jews who ascended to Eretz Yisrael at the end of the Galus of Bavel. When Rebbi Yehudah describes the borders of Eretz Yisrael, to which of these two sanctifications does he refer?
TOSFOS (DH v'Ashkelon) points out that Ashkelon was taken by the tribe of Yehudah (as mentioned in the beginning of Sefer Shoftim). When the Mishnah states that Ashkelon is considered Chutz la'Aretz, it is because the Olei Bavel did not capture it. According to Tosfos, the Mishnah describes the borders of Eretz Yisrael as sanctified by the Olei Bavel.
The RAMBAN here cites support for this understanding from the Sifri which lists "Techumei Eretz Yisrael Ad Makom she'Hecheziku Olei Bavel..." -- "The following are the borders of Eretz Yisrael as far as the Olei Bavel controlled...." The first and last places in the Sifri's list indeed are on the outskirts of Ashkelon ("Parashas Asheklon").
It is clear from various sources that the original conquest of Eretz Yisrael was initiated by Yehoshua, and it continued throughout the period of the Shoftim and beyond, until as late as David ha'Melech, who captured Syria (Aram Naharayim and Aram Tzova). The Gemara implies that Syria would have been considered part of Eretz Yisrael had it not been a "Kivush Yachid" (a conquest at the initiative of a single person -- in this case, David ha'Melech; see TOSFOS to Gitin 8a, DH Kivush).
The duration of the period from the beginning of the Olei Bavel until the destruction of the second Beis ha'Mikdash was approximately 440 years (see Megilah 11b). Throughout those years the borders of Eretz Yisrael were changing constantly due to conquests or treaties. Which conquests are considered the conquests of Olei Bavel with regard to the sanctification of the land (Kedushas ha'Aretz)? Does "the conquest of Olei Bavel" refer to the situation during the time of Ezra, or many years later during the reign of the Chashmona'im, or even later during the reign of King Herod (Hurdus), who ruled some 100 years before the destruction of the second Beis ha'Mikdash?
ANSWER: The answer to this question requires a review of the historical background of the time of the second conquest. When the Jews first returned to Eretz Yisrael from Bavel, they controlled a very small part of the land. The prophet relates that the Jews lived in the territories from Yerushalayim to Be'er Sheva (Nechemyah 11). The tribe of Binyamin lived in its portion, just north of Yerushalayim. It remains unclear whether or not there was any Jewish population at all in the Galil (the northern section of the country) at the time of Ezra.
The Gemara in Bava Metzia (28a) teaches that the land that was re-sanctified by Ezra included the land of Jews from all tribes, who resettled in their original locations. The Mishnah in Erchin (32a, and Gemara there) mentions that parts of Tzipori, Yodfat, and Gush Chalav were identified and sanctified by Olei Bavel.
The book of Maccabees relates that after the events of Chanukah, the Jewish population in Transjordan and in the Galil suffered from their hostile neighbors. In the year 3597 (163 BCE, or 230 years before the destruction of the second Beis ha'Mikdash), Yehudah ben Matisyahu ha'Chashmona'i went to Transjordan to defend his brethren, while he sent his brother Shimon to rescue the Jews in the Galil. This account is the first historical record of Jews living in the Galil during the time of the second Beis ha'Mikdash.
During the period from Ezra until the events of Chanukah, the province of Judea included only the inner, hilly region of the country. The entire coastal plain was populated by non-Jewish cities. It was only in the year 3619 (141 BCE, or about 210 years before the Churban), that Shimon captured the cities of Gezer and Yafo, thereby giving Judea the vital outlet to the Mediterranean Sea. His son, Yochanan Hurkenos, continued with conquests in the center of the country and along the coast. It is most probable that he was the king who connected Judea with the Galil. (His coins were found in the excavations of Yodfat. However, since he was the first Jewish king to mint coins, it is impossible to use this method to determine how far back in time Jews were living there.)
His son Yanai (who ruled from 103 to 76 BCE, about 170 years before the Churban) extended the boundaries even more. He captured the northern coast but failed to capture Ako. In the southern coastal plain he captured Azah (Gaza) and a place named Rinkorurah, which is identified as Al Arish. However, for political reasons he did not capture Ashkelon. Ashkelon remained a non-Jewish enclave and was never captured by Jews during the era of the second Beis ha'Mikdash. The Tosefta in Ohalos (ch. 18) mentions Ashkelon among the towns that are "Muvla" in Eretz Yisrael. In other words, it is surrounded by Eretz Yisrael but it is not a part of Eretz Yisrael. In the north, archeological evidence shows that Yanai captured the central section of what is commonly known as the Golan Heights, but he did not capture the northern section adjacent to Har Chermon.
In the year 3697 (63 BCE, 132 years before the Churban), the Romans captured Eretz Yisrael and wrested away from Jewish control most of the territories which were added by the Chashmona'i kings.
King Herod ruled during 3723-3756 (37 to 4 BCE, from 106 to 73 years before the Churban). Eventually, the Romans placed under his control all of the territories that were originally in Chashmona'i hands. They even added the northern Golan and the Bashan, Trachon and Churan regions, which are situated east of the Golan Heights. He did not control Ashkelon or Ako.
As the Ramban (mentioned above) points out, the three locations mentioned in the Mishnah here are among those mentioned in the "Beraisa d'Techumin" of the Sifri (Parshas Ekev) cited above, which lists the borders of Eretz Yisrael during the time of the second Beis ha'Mikdash. This "Beraisa d'Techumin" is also recorded in the Yerushalmi (Shevi'is 6:1). Approximately 25 years ago, a mosaic floor of an ancient synagogue was discovered near Beit Shean with an inscription recording this Beraisa, among others. Although there are a few discrepancies between the various sources, it is important to remember that this mosaic dates back further than any other manuscript in existence. Moreover, it was written near those locations mentioned in it and should therefore be considered most accurate.
The list, which begins from near Ashkelon, continues north along the coast until Ako and then heads inland. It mentions the city of Banyas, which is just south of the Chermon (under the name "Caeseria") and then mentions "Rekem Trachon Zimra d'Mitcham l'Botzrah" among others. In other words, the Beraisa clearly indicates that all territories under King Herod's control were considered conquests of Olei Bavel.
(The TEVU'OS HA'ARETZ disagrees and maintains that the Kedushah of Olei Bavel applies only to areas sanctified by Ezra. The KESEF MISHNAH and RAV YAKOV EMDEN (Chulin 7a) maintain that territories added later are also included. While the Kesef Mishneh refers to Yanai's conquests mentioned in Kidushin (66a), he does not refer to any Herodian conquests. Rav Yakov Emden does not refer to any specific conquests.)
II. THE MISHNAH'S OMISSION OF ALL BUT THREE BORDER TOWNS
QUESTION: Why does the Mishnah mention only the border towns of Ashkelon, Ako, and Rekem, and not any other borders of the country? Why does Rebbi Yehudah not quote the entire list as recorded in the Sifri?
(a) One possibility is that the Mishnah means that all of the area within these three cities is Eretz Yisrael. Although the northern boundary clearly continues past Ako, perhaps the Mishnah means that all areas within these three cities are certainly part of Eretz Yisrael, while some areas outside of these cities may or may not be part of Eretz Yisrael.
Although this explanation is plausible, Rav Zalman Koren points out that in those days there were no maps. It would have been impossible for people to know if their current location was north of Ako or south of Ashkelon.
(b) According to Rav Koren, the Mishnah's structure is addressed to a traveler delivering a Get. The cities mentioned in the Mishnah are along the main roads which lead to and from Eretz Yisrael. The Mishnah means that one who brings a get from Ashkelon or from south of Ashkelon, from Ako or from north of Ako, or from Rekem or from east of Rekem, must say "b'Fanai Nichtav." The Mishnah does not need to mention the other boundaries, because they are not situated along the main roads.
There is clear evidence that main roads to Eretz Yisrael led through Ako and Ashkelon (see Kesuvos 112a, "Kipi d'Ako"; Gitin 76b, "b'Ako Havu Mifteri"). Is there evidence that a main road led through Rekem? In order to answer this question, it is necessary to identify the place which the Mishnah calls "Rekem." (There were several cities named "Rekem." Indeed, the name "Rekem" appears twice in the Beraisa.)
Many scholars identify Rekem with the famous city of Petra, currently in southern Jordan. Rav Koren points out that this suggestion is very problematic. Petra was the capital of the Nabeteans, and at no time was it populated with Jews.
As mentioned above, the list of the boundaries in the Beraisa includes Rekem in the Trachon region. Interestingly, according to Josephus, King Herod chose to settle a group of people in the Trachon in order to protect the Olei Regalim who traveled from Bavel to Yerushalayim at the time of the festivals. In other words, the road eastward from Eretz Yisrael runs through the Trachon, and it is most probable that the city of Rekem mentioned in the Mishnah is the city of Rekem in the Trachon region mentioned in the Beraisa.
In summary, the Mishnah's depiction of the boundaries of Eretz Yisrael matches the description of the boundaries of Olei Bavel which reflects the Herodian conquests. The Mishnah lists the cities along the main roads that lead to and from Eretz Yisrael from the south, north, and east. Rekem is situated in the Trachon region in the northeastern section of Eretz Yisrael. Identifying Rekem as Petra is very problematic.
The passages which follow are a translation of the writings of Josephus (Antiquities of the Jews, Book XVII, Chapter 2), who writes about a Jew named Zimri who lived near the Trachon. It is very possible that this area could be identified with the city in the Beraisa d'Techumin called "Rekem Trachon Zimra d'Mitcham l'Botzrah (Bathyra?)."
"CONCERNING ZAMARIS, THE BABYLONIAN JEW...
1. AND now it was that Herod, being desirous of securing himself on the side of the Trachonites, resolved to build a village as large as a city for the Jews, in the middle of that country, which might make his own country difficult to be assaulted, and whence he might be at hand to make sallies upon them, and do them a mischief. Accordingly, when he understood that there was a man that was a Jew come out of Babylon, with five hundred horsemen, all of whom could shoot their arrows as they rode on horse-back, and, with a hundred of his relations, had passed over Euphrates, and now abode at Antioch by Daphne of Syria, where Saturninus, who was then president, had given them a place for habitation, called Valatha, he sent for this man, with the multitude that followed him, and promised to give him land in the toparchy called Batanea, which country is bounded with Trachonitis, as desirous to make that his habitation a guard to himself. He also engaged to let him hold the country free from tribute, and that they should dwell entirely without paying such customs as used to be paid, and gave it to him tax-free.
2. The Babylonian was seduced by these offers to come hither; so he took possession of the land, and built in it fortresses and a village, and named it Bathyra. Whereby this man became a safeguard to the inhabitants against the Trachonites, and preserved those Jews who came out of Babylon, to offer their sacrifices at Jerusalem, from being hurt by the Trachonite robbers; so that a great number came to him from all those parts where the ancient Jewish laws were observed, and the country became full of people, by reason of their universal freedom from taxes. This continued during the life of Herod; but when Philip, who was [tetrarch] after him, took the government, he made them pay some small taxes, and that for a little while only; and Agrippa the Great, and his son of the same name, although they harassed them greatly, yet would they not take their liberty away.
3. After a long time passed, Zamaris the Babylonian, to whom Herod had given that country for a possession, died, having lived virtuously, and left children of a good character behind him."
3) TWO "SHELUCHIM" WHO BRING A GET
QUESTION: Rabah and Rava disagree about the reason why a Shali'ach who brings a Get from Medinas ha'Yam needs to say, "b'Fanai Nichtav uv'Fanai Nechtam." Rabah explains that in Medinas ha'Yam, the scribes are not learned in the requirement of writing a Get Lishmah, and therefore the Shali'ach needs to testify that it was written Lishmah. Rava explains that when the Get is sent from Medinas ha'Yam, there are no witnesses available to validate (Mekayem) the Get's authenticity (since the witnesses of the Get are in Medinas ha'Yam).
The Gemara says that one practical difference between the two opinions exists in a case in which two Sheluchim bring the Get from Medinas ha'Yam together. According to Rava, they do not have to say "b'Fanai Nichtav," because they serve as the two witnesses who validate the Get's authenticity.
The Gemara is difficult to understand. Even if the two Sheluchim are able to validate the Get themselves since they constitute two witnesses, nevertheless if they do not say "b'Fanai Nichtav" they have not validated the Get. At some later time, after they leave the town, they will not be available to validate it when the need arises, and therefore they should be required to say "b'Fanai Nichtav" when they deliver it, even according to Rava. (TOSFOS, DH d'Asyuhah)
Moreover, the Gemara later (16a-17a) explains that the only situation in which two people who bring a Get do not have to say "b'Fanai Nichtav" is when they are both Sheluchim who were appointed by the husband to bring the Get. If only one of them was appointed as the Shali'ach to bring the Get and the other, who accompanies the Shali'ach, just happens to recognize the signatures on the Get, the Shali'ach still needs to say "b'Fanai Nichtav." According to Rava, why do both people have to be appointed as Sheluchim in order to be exempt from saying "b'Fanai Nichtav"? Even if neither one was appointed as a Shali'ach, the two people nevertheless are valid witnesses who are able to be Mekayem the Get, and therefore they should not need to say "b'Fanai Nichtav."
(a) TOSFOS and most Rishonim explain that whenever two witnesses bring a Get and claim that they were sent by the husband, Beis Din does not suspect that the Get is forged, and Kiyum (validation) of the Get is not necessary. Since two witnesses have testified that the husband sent them with the Get and that it was not forged by the woman, the Torah believes their word.
Why, though, are they believed as witnesses? Their testimony should be invalid because they are testifying about a fact concerning themselves (they are "Noge'a b'Davar")!
The Gemara later (5a, as explained by the CHASAM SOFER here) explains that the two emissaries are believed because they have a "Migu." Had they wanted to lie, they could have said that the husband divorced his wife in front of them (in which case they would not be testifying about themselves and would not be "Noge'a b'Davar"). Such testimony would have been accepted, since two witnesses are believed to say that the husband gave a Get to his wife. Now that they say instead that they are Sheluchim of the husband to deliver the Get, they are believed because of a "Migu."
The CHASAM SOFER cites the TESHUVOS HA'RE'EM who asserts that this must be Rashi's intention as well. The witnesses are not merely available to be Mekayem the Get, but they actually are Mekayem the Get when they say that the husband sent it with them (as the Gemara says on 5a).
When two people who did not bring the Get are available to be Mekayem the Get, the Shali'ach still must say "b'Fanai Nichtav" since the two people might leave the city and will not be available later to be Mekayem the Get in the event that the husband challenges it. For this reason, the Gemara says that only when the two people are Sheluchim who deliver the Get is there no need to say "b'Fanai Nichtav"; the very fact that they delivered the Get to the woman is an implicit testimony that the husband sent them and that the Get is not forged.
TOSFOS later (16a, DH Aval) writes that if a single Shali'ach brings a Get but he is accompanied by another person who testifies at the moment the Shali'ach hands over the Get that the husband sent him as well, it is not necessary to say "b'Fanai Nichtav." Apparently, this case is included in the case of "d'Asyuhah Bei Trei," since two people are testifying to the Shelichus at the time the Get is delivered.
TOSFOS here (2b, DH Mai) adds that if two people testify about the validity of the signatures in the Get and thereby validate the Get at any time before the Get is handed over, their testimony also exempts the Shali'ach from saying "b'Fanai Nichtav" (according to Rava). This case is also included in the case of "d'Asyuhah Bei Trei," since there is testimony about the validity of the Get at the time the Get is delivered.
(b) The wording of Rashi (DH Asyuhah, and 16b, DH Kasher), however, implies that it is not necessary for the Sheluchim to provide any testimony concerning the Get at the time they deliver it. Rather, since they are available to be Mekayem the Get if the husband challenges it, they do not need to say "b'Fanai Nichtav." How, then, does Rashi answer the questions posed earlier?
Moreover, according to Rashi, if the testimony of the two witnesses is that they recognize the signatures, how does Rashi understand the Gemara later (5a) which says clearly that the reason why two witnesses are believed is that they have a "Migu" that they could have said that the husband divorced his wife in their presence? The Gemara there implies that they testify that the husband gave the Get to them and not that they recognize the signatures. (They would not need a "Migu" to be believed that they recognize the signatures.)
Also, the RASHBA asks that, according to Rashi, the exemption from saying "b'Fanai Nichtav" should apply only when witnesses recognize the handwriting of the signatures on the Get. Why does the Gemara make no mention of this? Moreover, how do the judges of the Beis Din know to exempt the Sheluchim from saying "b'Fanai Nichtav" even before they ask the Sheluchim if they recognize the signatures? If the Sheluchim must first testify that they recognize the signatures in order to be exempt from saying "b'Fanai Nichtav," effectively they do need to testify at the time they deliver the Get!
The intention of Rashi cannot be that the two Sheluchim may deliver the Get to the woman in private and that they do not need to provide testimony at any time. If they deliver the Get in private, how will the woman be able to prove later that she received the Get from two agents of her husband, and thus that the testimony of "b'Fanai Nichtav" was not required, without bringing the Sheluchim themselves to testify?
Rather, Rashi may mean that it is not necessary for the two Sheluchim to say "b'Fanai Nichtav" or any other testimony at the time they deliver the Get (that is, they may deliver it in private). Before they leave the town, however, the woman must have them testify in Beis Din that they are Sheluchim who were appointed by her former husband to deliver the Get to her. (Their testimony in this regard is believed because of the "Migu" that they could have said that the husband divorced his wife in their presence, as mentioned above.)
The Chachamim instituted that "b'Fanai Nichtav" be said at the time the Get is handed over only when there is a single Shali'ach (5b, and Tosfos there, DH Yitleno). (The reason for this may be that the Shali'ach is more careful about his testimony ("Meidak Dayik") when he testifies at the time he delivers the Get. Alternatively, the woman might not realize that the testimony of a single witness will help her cause, and therefore the Chachamim instituted -- for her benefit -- that the Shali'ach must testify "b'Fanai Nichtav" at the moment he hands over the Get. Otherwise, the woman would not consider utilizing the Takanah that a single witness is valid for Kiyum of a Get.) In contrast, the Chachamim had no need to institute that "b'Fanai Nichtav" be said -- for the woman's benefit -- when two witnesses are available to be Mekayem the Get, there is no necessity to institute, because the woman knows to assume the responsibility to be Mekayem the Get and prevent the husband from claiming that it is forged.
Why must both people be Sheluchim in order to be exempt from saying "b'Fanai Nichtav"? A single Shali'ach should be exempt as long as there are two people in the city who recognize the signatures of the witnesses on the Get, since the woman now assumes responsibility for the Kiyum of the Get! Rashi later (16b, DH Kasher) explains that the Chachamim enacted their decree to say "b'Fanai Nichtav" as a "Lo Plug" and required a Shali'ach who delivers a Get to say "b'Fanai Nichtav" in all situations, because people who see a Shali'ach delivering a Get without saying "b'Fanai Nichtav" will not realize why the Chachamim exempted him. However, when two people bring a Get and together they hand the Get to the woman (see Rashi, end of 16a), it is clear to everyone why the Chachamim exempted them from saying "b'Fanai Nichtav" (that is, because they are two Sheluchim). Since it unusual for two people to deliver a Get, the Chachamim did not apply their enactment of "Lo Plug" in such a case (5a).
For the same reason, if the Shali'ach brings a Get which has already been validated, perhaps he still is required to say "b'Fanai Nichtav" lest onlookers not realize why the Get was accepted as valid without the Shali'ach saying "b'Fanai Nichtav." (M. KORNFELD)
Why does Rashi not explain like Tosfos, that when two Sheluchim deliver the Get and say in front of witnesses that they were appointed by the husband, their words serve in place of "b'Fanai Nichtav"? Rashi was bothered by the fact that the Gemara apparently does not require two Sheluchim to deliver the Get in front of witnesses altogether; they may deliver it in private if they want. Only a single Shali'ach must deliver the Get in front of witnesses (3a, 5b), as the TORAS GITIN (EH 142:18) and CHEMDAS SHLOMO point out.
(c) The TORAS GITIN (ibid.) and CHEMDAS SHLOMO suggest that even if the Sheluchim are no longer available, the husband who sent the Get does not know that. He will be afraid to come and challenge the Get, because he is under the impression that the two Sheluchim he sent are still in the city and will come and refute his claim and prove him wrong by testifying that he sent them. Since he will not challenge the Get, it is not necessary to say "b'Fanai Nichtav."
If the two witnesses who recognize the signatures on the Get were not sent by the husband, however, the husband will not be afraid that there are witnesses in the city who can refute his claim, and he will challenge the validity of the Get. Therefore, in such a case it is still necessary for the Shali'ach to say "b'Fanai Nichtav."
(See the RA'AVAD on the Rif who suggests another explanation for why two Sheluchim do not need to say "b'Fanai Nichtav.")