Exodus 25:12

And thou shalt cast for it four rings of gold, and set them upon its four corners; two rings for one side, and two rings for the second side.

AND THOU SHALT CAST FOUR RINGS OF GOLD FOR IT, AND PUT THEM IN THE FOUR ‘PA’AMOTHAV’ (CORNERS THEREOF). “The word pa’amothav is to be understood as the Targum rendered it: ‘corners thereof.’ It was on the upper corners near to the cover of the ark that the rings were placed. And two rings shall be on the one side of it, and two rings on the other side of it. These are the very four rings which are mentioned at the beginning of the verse, but here Scripture explains that two of these rings were placed on one side [and the other two on the other side].” Thus did Rashi explain, and he explained it well. But I do not know why Rashi wrote that “on the upper corners near to the cover” the rings were placed. For in that case, the weight [of the ark and the tables of law hanging down from the staves] would be very much heavier. Moreover, the respectful way is that the ark be lifted up, resting high upon the shoulders of the priests [when carrying it].
Rabbi Abraham ibn Ezra wrote: “I have searched in all Scripture and I have not found the term pa’am to mean ‘corner’ but only ‘foot.’ Thus: How beautiful are p’amayich’ (thy feet); the feet of the poor, ‘pa’amei’ (the feet of) the needy. Therefore I felt bound to explain that the ark had feet to it [upon which it rested].” And so Ibn Ezra explained the meaning of the verse to be that there were altogether eight rings, the four bottom ones according to that different version that Ramban’s questions on Ibn Ezra can be understood. Principally Ramban differs with three points that Ibn Ezra made: 1. That there were eight rings to the ark; 2. that the staves for carrying the ark were inserted in the upper rings; 3. that the ark had feet. — It is on this second point that the texts differ. It must then be remembered that Ramban is directing his criticism on Ibn Ezra holding that it was the upper rings that were for carriage. Ramban’s opinion is that the lower rings were for the insertion of the staves with which the ark was carried. Ramban will also differ with Ibn Ezra on the other two points. being those through which the staves were inserted to carry the ark with, whilst the four upper rings were purely for ornamental purposes. His words are, however, not at all correct. For if, as he said, pa’am means foot, then Scripture is commanding that the rings should be in the lower corners upon which the ark rests, and these bottom corners are called “feet” because …

ויצקת לו, they would protrude beyond the outer edges of the Ark and not be an integral part of it.

ושתי טבעות, of the total of four such rings.

על צלעו האחת, along the width of the Ark (the shorter side) seeing that the staves protruded in the direction of the sanctuary (backwards, seeing the Ark itself was in the inner sanctum) The length of the Ark had to be positioned in a north/south direction so that the staves would face east/west.

פעמותיו, the corners at its outer edges.

ושתי טבעות על צלעו האחת, the side, wall of the Ark, is called צלע. G’d had commanded therefore that these rings be attached at the four corners of the Ark. G’d therefore commanded that there were to be four such rings at the four corners. Furthermore, G’d commanded that they not be attached along the short sides of the Ark but along the long sides of the ark. [this contradicts the commentary of both Rashi and Rash’bam. Ed.]