"closed portion" (setumah) with the Hebrew letter "ס" (samekh), often in place of the visual gap in the line. Rough English equivalents are "P" and "S" respectively. In masoretic codices and in medieval scrolls, these two spacing techniques allowed for a larger range of options: An "open portion" always started at the beginning of a new line. This could happen the way described above, but also by leaving a blank line between the two portions, thus allowing the previous portion to sometimes entirely fill its last line of text. A "closed portion" never began at the beginning of a line. This could happen as in modern scrolls (a space in the middle of a line), but also by the previous portion ending before the end of the line, and the new portion beginning on the next line after an indentation. Open portions often seem to reflect the beginning of a new topic or a major subdivision within a biblical book, while closed portions seem to reflect smaller units or minor subdivisions. Most printed Hebrew bibles today represent the parashot using the more limited techniques found in typical modern Torah scrolls: A space in the middle of a line for a closed portion, and beginning at the start of the next line for an open portion (not a blank line). A notable exception is The Jerusalem Crown (The Bible of the Hebrew University of Jerusalem, 2000), whose typography and layout is fashioned after the Aleppo Codex, and follows the medieval spacing techniques for parashah divisions by leaving an empty line for {P} and starts {S} on a new line with an indentation. Medieval Ashkenazic sources beginning with the Mahzor Vitry also refer to a third spacing technique called a parashah sedurah. This involved starting a new parashah at the same point in the line where the previous parashah ended on the line above. Halakhic significance Validity of scrolls According to the ruling of Maimonides (Laws of Tefillin, Mezuzah and Torah Scrolls 10:1), any error regarding a parashah completely invalidates a Torah scroll. This includes a parashah in the wrong place, of the wrong type, or a missing parashah. However, there is also a responsum by Maimonides in which he ruled that one may recite a blessing over reading from an invalid scroll, based on the reasoning that the commandment is in the reading itself, not in the text being read from.