יורה דעה רפ״בYoreh De'ah 282

Se’if 1א׳

חַיָּב אָדָם לִנְהֹג כָּבוֹד גָּדוֹל בְּסֵפֶר תּוֹרָה. וּמִצְוָה לְיַחֵד לוֹ מָקוֹם וּלְכַבֵּד הַמָּקוֹם הַהוּא וּלְהַדְּרוֹ בְּיוֹתֵר. וְלֹא יִרֹק כְּנֶגֶד סֵפֶר תּוֹרָה. וְלֹא יְגַלֶּה עֶרְוָתוֹ כְּנֶגְדּוֹ. וְלֹא יִפְשֹׁט רַגְלוֹ כְּנֶגְדּוֹ. וְלֹא יַנִּיחֶנוּ עַל רֹאשׁוֹ כְּמַשּׂוֹי. וְלֹא יַחֲזֹר אֲחוֹרָיו, אֶלָּא אִם כֵּן גָּבוֹהַּ מִמֶּנּוּ עֲשָׂרָה טְפָחִים, אֶלָּא יֵשֵׁב לְפָנָיו בְּכֹבֶד רֹאשׁ וּבְיִרְאָה וָפַחַד, שֶׁהוּא הָעֵד הַנֶּאֱמָן עַל כָּל בָּאֵי עוֹלָם, שֶׁנֶּאֱמַר: וְהָיָה שָׁם בְּךָ לְעֵד (דְּבָרִים לא, כו), וִיכַבְּדֶנּוּ כְּפִי כֹּחוֹ.

Respectful behavior toward a Torah scroll, and the law of its use. Herein are contained 19 sections: One must behave with great respect toward a Torah scroll, and is commanded to designate a special place for it which one must treat with respect and which one must decorate (beautify) greatly. One may not spit in front of a Torah scroll, nor may one undress (to the point of nudity) in front of it, nor may one scuff one’s feet (on a dirt floor) in front of it, nor may one place it upside down. Also, one may not turn one’s back on it unless it is [sitting on something] ten handbreadths higher [than the person is tall – to be above the turned back]. Rather, one should sit before it with the proper mindset (for prayer), and with awe and fear, since this (Torah scroll) is [considered] the trusted witness regarding [the deeds of] all who live on earth, as it is said, “(Take this book of the Teaching [which can also be read: ‘Take this Torah scroll’] and place it beside the Ark of the Covenant of Adonai your God,) and let it remain there as a witness against you.” (Deuteronomy 31:26), and one should respect it according to its power.

Se’if 2ב׳

הָרוֹאֶה סֵפֶר תּוֹרָה כְּשֶׁהוּא מְהַלֵּךְ, חַיָּב לַעֲמֹד לְפָנָיו, וְיִהְיוּ הַכֹּל עוֹמְדִים עַד שֶׁיַּעֲמֹד זֶה שֶׁמּוֹלִיכוֹ וְיַגִּיעֶנּוּ לִמְקוֹמוֹ, אוֹ עַד שֶׁיִּתְכַּסֶה מֵעֵינֵיהֶם. הַגָּה: אֲבָל לִפְנֵי חֻמָּשִׁים שֶׁלָּנוּ אֵין צְרִיכִים לַעֲמֹד (ב"י בְּשֵׁם הָרַמְבַּ"ם). וְיֵשׁ מַחְמִירִים (רשב"א סי' קמ"ד). הַשּׁוֹמֵעַ קוֹל הַנּוֹשֵׂא סֵפֶר תּוֹרָה אַף עַל פִּי שֶׁאֵינוֹ רוֹאֶה אוֹתוֹ, חַיָּב לַעֲמֹד (ב"י בְּשֵׁם הָרַב רַבֵּנוּ מָנוֹחַ).

If one sees a Sefer Torah in motion, one must stand before it, and all should stand until the one carrying it stops and brings it to its place, or until it is visually obscured with a cover. Rema: But before our "Chumashim" one does not need to stand (B"Y citing Rambam), although some are stringent (Rashb"a 144). If one hears the voice of the one carrying the Sefer Torah, even if one cannot see them, one must stand (B"Y citing R' Rabbeinu Manoach).

Se’if 3ג׳

הָיָה הוֹלֵךְ מִמָּקוֹם לְמָקוֹם וְסֵפֶר תּוֹרָה עִמּוֹ, לֹא יַנִּיחֶנוּ בְּשַׂק וְיַנִּיחֶנּוּ עַל גַּבֵּי חֲמוֹר וְיִרְכַּב עָלָיו, אֶלָּא מַנִּיחוֹ בְּחֵיקוֹ כְּנֶגֶד לִבּוֹ וְהוּא רוֹכֵב עַל הַחֲמוֹר. וְאִם הָיָה מְפַחֵד מִפְּנֵי הַגַּנָּבִים, מֻתָּר.

If one is walking from place to place and a Sefer Torah is with one: one should not set it to rest in a marketplace/in sackcloth, or on the back of a donkey and ride upon it, but rather, one should set it to rest in all its accoutrements, opposite one's heart, and it should ride on the donkey by itself. And if one is afraid of thieves, it is permitted.