How the Torah Came to Be Written in Assyrian Script

Mar Zutra said, Mar Ukba said: At first the Torah was given to Israel in Hebrew script and the holy tongue; it was given to them again in the days of Ezra in Assyrian script and the Aramaic language; Israel chose for themselves the Assyrian script and the holy tongue. It was taught: Rabbi Yose says: Ezra was worthy that the Torah be given through him, had Moses not preceded him. And although the Torah was not written through him, the script was changed through him, as it is written, "and the writing of the letter was written in Aramaic" (Ezra 4:7), and it is written, "and they could not read the writing" (Daniel 5:8), and "and he shall write for himself a copy [mishneh] of this Torah" (Deuteronomy 17:18), a script fit to be changed [mishtaneh]. And why is it called Assyrian [Ashurit]? Because it came up with them from Assyria. Rabbi says: In this very script was the Torah given; once they sinned it was turned to a debased form for them; once they repented it was restored to them, as it is said, "return to the stronghold, you prisoners of hope" (Zechariah 9:12). And why is it called Assyrian [Ashurit]? Because it is the most confirmed and upright [me'ushar] of scripts. Rabbi Shimon ben Elazar says in the name of Rabbi Elazar ben Perata, who said in the name of Rabbi Elazar of Modi'in: This script was not changed at all, as it is said, "the hooks of the pillars" (Exodus 27:10); just as the pillars were not changed, so the hooks [vavin, the letter vav] were not changed. And it says, "and to the Jews according to their writing and according to their language" (Esther 8:9); just as their language was not changed, so their writing was not changed. Then how do I uphold "a copy [mishneh] of this Torah"? Two Torahs, one that goes out with him and so forth, and one that is laid up for him in his treasury.