Petuḥa, setuma, and the inverted nuns
1. The Rambam and the Rosh differ as to the definition of petuḥa and setuma, and one who is God-fearing will take care to make them in such a way as to satisfy both opinions. That is, for a petuḥa paragraph one finishes the paragraph before it in the middle of the line, leaving a gap of nine letters – that is, a blank space sufficient to write “asher” three times in the script he’s using for the writing, or nine yuds if circumstances press – and starts the petuḥa paragraph at the beginning of the next line. For a setuma paragraph, one finishes the preceding paragraph at the beginning of the line, leaves a gap big enough to make letters, and starts the setuma paragraph towards the end of that line. This formation is correct according to both the Rambam and the Rosh (see Excursus 16).
2. But if one cannot do it like this, one should stay with the Rambam’s method. He wrote that if one had little or no space at the end of the line before the petuḥa paragraph, he should leave the next line blank, and start the petuḥa paragraph at the beginning of the third line. This applies also if the paragraph before the petuḥa was going to finish on the penultimate line of a column – he leaves the bottom line blank; and also if the paragraph before the petuḥa finished on the last line of a column – he leaves the top line of the next column blank and starts to write on the second line of the column, so that there will be a blank line between the paragraphs (according to the Rosh, all these count as stumot).
3. If one didn’t have space to finish a setuma paragraph, leave a sufficiently large gap, and commence writing the next paragraph all on the same line, he should leave all the rest of the line blank, and start the next line a little way in, leaving space at the start of the line. If the gap at the end of the line was shorter than nine letters, he makes up the distance at the beginning of the second line, so that the combined length of both comes to nine letters. If the previous paragraph went all the way to the end of the line, he should leave the whole distance at the beginning of the second line, and start writing in the middle of the line (according to the Rosh, this is petuḥa). So we can say that a petuḥa paragraph always starts at the beginning of a line and a parsha setuma always starts in the middle of a line. This is the Rambam’s approach, and the posekim take it to be the correct one.
4. It is invalid to make a setuma where one should have made a petuḥa or a petuḥa where one should have made a setuma; to leave a gap where there is no paragraph break at all; or to write it properly but omit to leave a break where there should have been a break. There is no remedy but to replace the whole column, but some say it may be corrected just like any other error, and it is the custom to cut it out where this is possible without damaging the Name. But one may not cut out the Name and make holes in the sheet (see chapter 11:8). The sofer should be very careful, if at all possible, that when he rewrites he should match the new lettering to the old, so that the repair will not be conspicuous (Taz). If one left a gap where there is no paragraph break because it wasn’t possible to write on the place, for instance if there was a seam or a tear, or even a patch if one holds that one may not write on a patch, it is clear that he didn’t leave the gap for the purpost of making a break between paragraphs, and there is the possibility of leniency.
5. Although as a general rule we follow the Rambam, should we find a sefer which does not, we don’t need to declare it invalid. Whether the typographical formation of the petuḥot and stumot are different or whether its paragraphs themselves differ from Rambam’s list of which are the petuḥot and stumot, post facto we can permit its use, since in some places there are authorities with different opinions. Accordingly, even in a place where no-one disagrees with the Rambam, we may say that that sefer Torah was written on the authority of someone who disagreed with the Rambam. This applies only if the sefer was not written in accordance with the opinion of the Rambam, since then we can attribute it to some other authority; if we find a divergence from Rambam’s opinion which we know to be a scribal error since no-one at all holds otherwise, it is probably invalid even post facto (Sha”kh).
6. A further comment concerning permitting use of paragraph formations which aren’t according to the opinion of the Rambam: whichever opinion you choose, you have to say that the entire Torah was written that way, so that the different versions don’t work against each other – so if one switches about, and makes one formation sometimes petuḥa like the Rambam and sometimes setuma like the Rosh, the sefer Torah is definitely invalid (Benei Yonah).
7. In the section “Vayhi binsoa ha-aron,” one makes two special nuns, and the posekim are divided as to exactly how. The idea is – theoretically and practically – to make them in the gaps which are between the paragraphs. So that the gap between paragraphs should be of an adequate size, this is what one should do: after the conclusion of “min ha-maḥanei” (the paragraph before “Vayhi binsoa”) he should leave a nine-letters’ gap; write the special nun; leave a two- or three-letters’ gap; start writing “vayhi binsoa” on that line, as for a setuma paragraph; after concluding “alfei yisrael” leave another two- or three-letters’ gap; write the special nun; leave a nine-letters’ gap on that line; and start “vayhi ha-am” at the beginning of the next line. This covers all the possibilities (Noda be-Yehuda kamma 74, also Benei Yonah & Minḥat Shai write that the idea is not to invert the nun of “binsoa” and of “ke-mit-onnaim” as the Maharshal says).
8. Some say that the nun is basically like an ordinary nun except that the leg faces backwards, and some turn the nun entirely backwards (these two constructions are brought in the Ohr Torah, and he rules with the second, but the Noda be-Yehudah rules the first). If one didn’t do anything at all to these nuns, the sefer may be declared valid post facto (Responsa of the Maharam of Lublin, and the Benei Yonah – not like the Maharshal) (See Excursus 17).