שמות, פרק כ״ח, פסוק כ״ו

To ensure the garments of the High Priest were worn in a stable and dignified manner, the breastpiece required a secure attachment to the ephod at its lower base, not just at the top. Without this lower anchor, the heavy breastpiece would hang loosely, swinging out of place and knocking against the High Priest's stomach with his every movement [מלבי״ם, רש״ר הירש].

The primary approach among commentators is that the rings used for this connection were fastened to the two bottom corners of the breastpiece, on the right and the left. This lower edge rested directly against the ephod at the waist, entirely distinct from the upper edge positioned near the neck [רש״י, ביאור יש״ר, חזקוני, בכור שור]. The purpose of these rings was to firmly bind the breastpiece to the ephod using a blue thread. According to Jewish law, this bond creates a permanent connection that is strictly forbidden to ever be severed [רש״ר הירש].

These lower rings were specifically placed facing inward, toward the body of the High Priest and the ephod, rather than being visible on the outside [רש״י, קאסוטו, שטיינזלץ, חזקוני]. This inward placement was a direct result of the unique structure of the breastpiece, which was fashioned from a folded piece of cloth designed to hold the Urim and Thummim inside [בכור שור, קאסוטו].

A fascinating perspective highlights the mechanical difference between the top and bottom rings based on this folded design. The opening of the folded breastpiece faced upward so its sacred contents would not fall out. Consequently, the top rings were attached to the outside of the cloth to pinch the opening shut and safely secure what was inside. At the bottom, however, where the fabric fold was naturally closed, the rings were positioned on the inside. This hidden placement allowed for a much tighter, more stable connection to the ephod beneath it [מלבי״ם].