Our Mishnah states 'Get Pashut Eidav mi'Tocho'. A 'Get Pashut' is a plain Sh'tar (in fact, every document is called a Get).

In a Get Mekushar, every second line is left blank, with the written line folded over the blank one, which is then stitched and knotted, and at the back of which, a witness signs.

Our Mishnah distinguishes between a Get Pashut and a Get Mekushar - inasmuch as the former is signed on the inside, and the latter, on the outside.

If one confuses the two, according to the Tana Kama, and signs the witnesses on the outside of a Get Pashut or on the inside of a Get Mekushar - both are Pasul.

Rebbi Chanina ben Gamliel validates the latter - because it is possible to untie the knots and turn it into a Get Pashut.

According to Rabban Shimon ben Gamliel - one simply follows the local custom regarding Sh'taros (as will be explained in the Sugya).

The minimum number of witnesses who must sign on a ...

... Get Pashut is two.

... Get Kashur is three.

In the case of a Get Mekushar, a 'Get Kere'ach' - one that contains more knots than witnesses, is Pasul, too.

The 'Pashut she'bi'Mekushar' (which will be discussed shortly) is - the Tofeis (the part of the Sh'tar that is prewritten by the Sofer), which is written in the form of a Get Pashut.

Rebbi Chanina learns from the double expression in the Pasuk in Yirmiyah ...

... "Sados ba'Kesef Yiknu ve'Chasov ba'Sefer, ve'Chasom" that - there are two kinds of Sh'tar; "ve'Chasov ... " implies a Get Pashut, and "ve'Chasom", a Get Mekushar.

... "ve'Ha'ed Eidim" that - the former requires two witnesses ("ve'Ha'ed"), and the latter, three ("Eidim").

Whereas Rafram learns from the Pasuk ...

... "va'Ekach es Sefer ha'Miknah" - a Get Pashut, from "es he'Chasum - a Sh'tar Mekushar, and from "ve'es ha'Galuy" - the Pashut she'bi'Mekushar.

... "ha'Mitzvah ve'ha'Chukim" that - the two Sh'taros have different Dinim.

Rami bar Yechezkel learns the two Sh'taros from the double Lashon in the Pasuk (in Parshas Shoftim) -"al-Pi Shenayim Eidim O al-Pi Sheloshah Eidim Yakum Davar".

According to all three opinions we know that it is a Get Mekushar that requires three witnesses and a Get Pashut, two, and not vice-versa - because logically speaking, since the former has 'more' knots, one would expect it to have more signatures, too.

We query all three sources for the two kinds of Sh'tar on the grounds that - the Pesukim concerned are all needed for their own issues.

The Pasuk ...

... "Sados ba'Kesef Yiknu ... " came as a sound piece of advice on the part of Yirmiyah to document sales of land, and have them signed, in anticipation of the impending Galus Bavel, which might result in witnesses not being available to testify personally after their return from Galus (as we learned in a Beraisa).

... "va'Ekach es Seifer ha'Miknah ... " that - Yirmiyah followed his own advice.

... "al-Pi Shenayim Eidim ... " - to compare three witnesses to two, as explained by Rebbi Akiva and the Rabbanan according to their respective opinions in Makos (see Rabeinu Gershom).

In that case, the Pesukim are an 'Asmachta' and Get Mekushar is a Takanas Chachamim which Chazal instituted - on account of Kohanim, who were known to be short-tempered, and who would divorce their wives in a fit of temper. Then, after the event, when it was too late (seeing that a Kohen is forbidden to marry a divorcee), they would regret what they had done (see Tosfos DH 'Tiknu').

What they expected to gain with this Takanah was - the fact that a Get Mekushar takes a long time to write, and hopefully, in the interim, the Kohen would calm down and retract.

They extended the Takanah to cover all Sh'taros, despite the fact that the reason is confined to Gitin - in order not to differentiate between one Sh'tar and another.

According to Rav Huna, the witness would sign on a Get Mekushar between one knot and the next (on the blank space), whereas according to Rebbi Yirmiyah bar Aba - he would sign at the back of the writing.

We initially understand Rav Huna's statement to mean - on the blank space on the inside of the Sh'tar (see Tosfos DH 'le'Rav Huna').

When a Get Mekushar was brought before Rebbi (who was unfamiliar with a Get Mekushar), and he expressed surprise that it did not contain a date, his son Rebbi Shimon suggested that - perhaps it was absorbed in the space between the knots.

Therefore to expose the date - Rebbi cut the knots.

Rami bar Chama queried Rav Huna from the previous episode with Rebbi on the grounds that - if the signatures appeared on the inside of the Sh'tar, as we initially thought, why did he not express equal surprise that the Sh'tar contained no signatures?

Rav Chisda replied that, when Rav Huna said 'between the knots' - he meant on the outside of the Sh'tar, where they were immediately visible.

The problem with Rav Huna, bearing in mind that the witnesses signed at the back of the blank space, leaving the latter part of the Sh'tar unsigned is - what is to stop the creditor from adding any clause that suits him on to the Sh'tar?

This is not a problem according to Rebbi Yirmiyah bar Aba - because, in his opinion, the witnesses signed at the back corresponding to the writing on the other side right down to where the writing terminated. Consequently, if anything was added to the Sh'tar after that, it would be noticeable and would be Pasul.

We answer the Kashya on Rav Huna by pointing out that - wherever the Sh'tar ended, they would add the words 'Sharir ve'Kayam', and anything that was added after that was Pasul.

We are not afraid that he will add a clause on to the end of the Sh'tar and conclude with a second 'Sharir ve'Kayam' - because only one 'Sharir ve'Kayam' is permitted on a Sh'tar, and no more.

Nevertheless, even if one writes 'Sharir ve'Kayam' only once, we are still afraid that he may erase 'Sharir ve'Kayam' and add in its place a clause of his choosing, before adding 'Sharir ve'Kayam' after the clause.

We answer with a statement by Rebbi Yochanan, who says that a Sh'tar that has a word or two that are ...

... 'hanging' between the lines - it is Kosher, provided that this is substantiated at the end of the Sh'tar.

... erased he invalidates - even if it is substantiated at the end of the Sh'tar.

If some words on a Sh'tar are erased, the Sh'tar up to the erased words is Kasher (Rashash).

Even the entire Sh'tar will be Kosher however, even if one or two words have been erased - provided those words are not in a location where one would expect to find 'Sharir ve'Kayam', or even if they are, if the space is too small to have contained those two words.