We ask whether the two blank lines (that invalidate a Sh'tar) include the spaces or not. Rav Nachman bar Yitzchak concludes that - the two blank lines (that invalidate a Sh'tar) must include the spaces, because what can one do with lines without spaces?

Rebbi Shabsi in the name of Chizkiyah requires the two lines space to be the size of the witnesses' hand-writing (meaning not that of the Sofer) - because, due to the un-likelihood of the Sofer (who generally has a smaller script than an inexperienced layman) agreeing to forge the Sh'tar, the owner would have to do it himself.

Rebbi Yitzchak ben Elazar (who does not dispute Chizkiyah on principle) gives the Shiur of space as 'Lech' 'Lech' written one on top of the other. The significance of these two letters is - that the 'Lamed' towers above the line, whereas the final 'Chaf' drops below it (in which case extra space is required, to accommodate the top of the 'Lamed' on top of the top line, the bottom of the 'Chaf' below the bottom one, and the top of the 'Lamed' and bottom of the 'Chaf in between the two lines.

Rebbi Chiya bar Ami in the name of Ula, who gives the Shiur as a 'Lamed' above and a 'Chaf' below - requires two lines and only three spaces; whereas Rebbi Yitzchak ben Elazar requires two lines and four spaces (two between the two lines of writing).

According to Rebbi Avahu, the Shiur of two lines is equivalent to one line and two spaces. The example he gives for this is - 'Baruch ben Levi' on one line (which contains a 'Chaf' protruding below the line and a 'Lamed' above it).

Rav differentiates between the previous Din, where the two lines space is left between the contents of the Sh'tar and the witnesses' signatures, and where the space is left between the signatures and the Asharta (de'Dayna) - the Beis-Din's verification of the Sh'tar (which is also known as a Henpek').

He validates the latter case - on the grounds that they would fill in the space between the signatures and the Asharta with ink (rendering it impossible to write anything there).

They not do the same thing between the Sh'tar and the witnesses signatures - because the witnesses tend to sign on the last thing in the Sh'tar, without necessarily inquiring as to its meaning. Consequently, they would simply sign on the ink-mark (instead of on the contents of the Sh'tar).

We are not afraid that the Beis-Din will sign on the ink-mark - since Beis-Din tend to sign on the contents of the Sh'tar, and not on whatever appears last on the Sh'tar.

We query the previous statement of Rav (validating a two-line space between the witnesses' signatures and the Asharta) however, on the suspicion that the creditor might then be tempted to cut off the top half of the Sh'tar, erase the ink-mark and fill in the space with whatever suits him, and Rav himself said that - a Sh'tar which is written and signed on erased parchment is Kasher.

This Kashya is based on Rav Tivyumi's text of that statement (citing the author as Rav), but does not present a problem according to Rav Kahana - who cites Shmuel as the author (permitting us to explain that Rav will invalidate it).

And we answer that a Sh'tar that is written and signed on erased parchment, - is not substantiated by means of the Asharta, but by the witnesses.

Rebbi Yochanan takes the exact opposite view (from Rav). According to him, a Sh'tar with one blank line between the witnesses' signatures and the Asharta - is Pasul ...

... because we are afraid that the claimant will cut off the top of the Sh'tar, and write a fresh one together will the signatures on the last line. And a Sh'tar that is written and signed by the witnesses on one line is Pasul, in his opinion.

He concedes however, that one line between the Sh'tar and the witnesses' signatures is Kasher - because he holds that a Sh'tar that is written on one line and signed on the next is Pasul (and therefore there is nothing to be afraid of) ....

... because of the principle cited earlier that - we do not learn from the last line. Consequently, he is afraid that the claimant will cut off the top of the Sh'tar, leaving only the last line followed by the signatures of the witnesses.

This prompts us to ask - why do we not invalidate a regular Sh'tar with the last line blank and the witnesses' signatures underneath (bearing in mind the suspicion that he will cut off the top of the Sh'tar, write in the one blank line whatever he wants together with the witnesses and verify it via the original witnesses).

And we answer that - any Sh'tar that is written and signed on one line can only be substantiated by the witnesses on that line.