The mention of Lashon Ashuri, or Assyrian language, is referenced twice in the Tractate Megillah, in Megillah 17a:9 and Megillah 18a:23, where the Rabbi interchanges Ashuri with Hebrew. Hebrew is also referred to as Lashon Hakodesh, or Holy Tongue. The interchanging of Ashuri with Hebrew prompts the understanding that Ashuri, Hebrew, and Lashon Hakodesh are one and the same language.
Ktav Ashuri (Hebrew: כְּתָב אַשּׁוּרִי, ktav ashurí), or Assyrian script, is a traditional calligraphic form of the alphabet shared between Hebrew and Aramaic. Over some centuries, certain ornaments were simplified or removed for use outside traditional religious calligraphy, to become the modern print form of the Hebrew alphabet, which it most closely resembles.
Mention of the Ashuri script first appears in rabbinic writings of the Mishnaic and Talmudic periods, referring to the formal script used in certain Jewish ceremonial items, such as sifrei Torah, tefillin, and mezuzot. Also sometimes called the "square" script, the term is used to distinguish the Ashuri script from the Paleo-Hebrew alphabet.
The Talmud gives two opinions for why the script is called "Ashuri": either because the Jews brought it back with them when they returned from exile in Assyria; or alternatively, this script was given at Sinai and then forgotten and eventually revived, and received its name because it is "meusheret" (beautiful/praiseworthy or authorized).
Ritual use of the scriptEdit
There are many rules concerning the proper formation of letters if the written text is to be valid for religious purposes.
Ashkenazi, Sephardi, Mizrahi, and Yemenite Jews each have their own calligraphic tradition regarding certain details of how each letter is formed, although the overall shape is similar. Generally, while each tradition favors their own calligraphic style, none consider the other traditions passul (invalid) for Torah scrolls or any other ritually used scroll or parchment.
Samaritans maintain a calligraphic tradition different from the Ashuri script, using instead the Paleo-Hebrew alphabet they employ for their scriptures.