In describing the design of the aron, the Torah says:
וְיָצַ֣קְתָּ לּ֗וֹ אַרְבַּע֙ טַבְּעֹ֣ת זָהָ֔ב וְנָ֣תַתָּ֔ה עַ֖ל אַרְבַּ֣ע פַּֽעֲמֹתָ֑יו וּשְׁתֵּ֣י טַבָּעֹ֗ת עַל־צַלְעוֹ֙ הָֽאֶחָ֔ת וּשְׁתֵּי֙ טַבָּעֹ֔ת עַל־צַלְע֖וֹ הַשֵּׁנִֽית׃
And you should cast four rings of gold for it, and put them in its four pa’amos; and two rings shall be on its one side, and two rings on its other side.
The word “pa’amosav” is difficult to translate. Rashi, following Unqelus, renders it “corners”. But the Ibn Ezra and Chiquni note that the word is never otherwise used to mean corners. They each cite
תִּרְמְסֶ֖נָּה רָ֑גֶל רַגְלֵ֥י עָנִ֖י פַּֽעֲמֵ֥י דַלִּֽים׃ -ישע’ כו:ו
צֶ֭דֶק לְפָנָ֣יו יְהַלֵּ֑ךְ וְיָשֵׂ֖ם לְדֶ֣רֶךְ פְּעָמָֽיו׃ –תה’ פה:יד
מַה־יָּפ֧וּ פְעָמַ֛יִךְ בַּנְּעָלִ֖ים בַּת־נָדִ֑יב חַמּוּקֵ֣י יְרֵכַ֔יִךְ כְּמ֣וֹ חֲלָאִ֔ים מַֽעֲשֵׂ֖ה יְדֵ֥י אָמָּֽן׃ –שה״ש ז:ב
In these and many other cases, the word pa’am is used to mean leg. In Yeshaiah, it is paralleled with “regel“, in Tehillim, it is something with which one walks, and in Shir haShirim, it wears shoes.
On Friday night, Rav Aharon Cohen’s devar Torah was based on a seifer called Areshes Sefaseinu. He asks why the pasuq would use the word “pa’amosav” rather than the far more common “raglav”?
Angels are stationary, which is why the prophet describes them as “standing upon one regel“. See the idea in greater depth in this post on the travels of parashas Mas’ei. Regel connotes the ability to stand, stability. Tables have raglayim.
We see from the pasuq in Tehillim that the Ibn Ezra uses, “and he will place his feet on the path”, that pa’amos has a greater connotation of legs as a means of motion. This is more like the nature of people than of angels. People move, we progress. (I also discuss the difference in the essay “People and Angels“. And in this article for Mesukim MiDevash, I try to relate them to the placement of the instruments in the Mishkan.)
The aron‘s role in the Miskan parallels that of the soul in the body. Therefore, the Areshas Sefaseinu suggests, it has pa’amos, not raglayim.
I was thinking about the etymology of the words. Regel also connotes regilus, regularity, and hergel, habit. It is looking at the repetitious rhythm of walking. A pa’am is a time, a notable event.
What causes stagnation? When one looks only at the mechanics of the mitzvos, following them out of habit or culture. To grow as people, each performance must be done with
intent for forward motion, to concentrate on this particular encounter with G-d as an event.