Learning During Kriat HaTorah. The Person and the Page. Sotah 39a

Sotah 39a describes and derives the obligation to be quiet for keriat haTorah. Thus:

אָמַר רָבָא בַּר רַב הוּנָא: כֵּיוָן שֶׁנִּפְתַּח סֵפֶר תּוֹרָה אָסוּר לְסַפֵּר אֲפִילּוּ בִּדְבַר הֲלָכָה, שֶׁנֶּאֱמַר: ״וּבְפִתְחוֹ עָמְדוּ כׇּל הָעָם״, וְאֵין עֲמִידָה אֶלָּא שְׁתִיקָה, שֶׁנֶּאֱמַר: ״וְהוֹחַלְתִּי כִּי לֹא יְדַבֵּרוּ כִּי עָמְדוּ לֹא עָנוּ עוֹד״. רַבִּי זֵירָא אָמַר רַב חִסְדָּא, מֵהָכָא: ״וְאׇזְנֵי כׇל הָעָם אֶל סֵפֶר הַתּוֹרָה״.

“Rava bar Rav Huna” is simply an alternate spelling of “Rabba bar Rav Huna”, a third-generation Amora who took over Sura academy after his father, Rav Huna, passed away. He said that once the sefer Torah is “opened” (whatever that means), it is forbidden to speak to one another, even in a matter of halacha. His source