שמות, פרק כ״ז, פסוק ה׳

The copper altar in the Tabernacle required a precise combination of architectural elements to serve both practical and ritual purposes. A defining feature of its exterior was a unique ledge or rim that completely surrounded the structure. Commentators offer different perspectives on the exact nature of this feature. One approach suggests it was a decorative groove or protrusion, similar to the ornamental carvings typically found on wooden vessels [ספורנו, רש״י, מלבי״ם]. Although such features are sometimes associated with round objects, here it entirely surrounded the square shape of the altar [ברכת אשר]. Another perspective views this element as a foundational step or base upon which the upper layers of the altar rested [רש״ר הירש]. In practice, this rim either served as a horizontal visual ornament [ביאור שטיינזלץ, קאסוטו] or as a functional walkway for the priests [רשב״ם]. To reconcile these ideas, some explain that there were actually two distinct ledges: a practical walkway at the very top to allow priests to move safely without slipping, and a decorative protrusion lower down on the outer wall [רש״י, תורה תמימה, חזקוני].

A copper net was suspended beneath this outer decorative ledge. Rather than sitting completely flush against the rim, it was positioned a slight distance below it [העמק דבר]. The specific terminology used to describe this net hints at the concept of separate domains, as it effectively divided the altar into two distinct zones [הכתב והקבלה]. Structurally, the lower half of the altar may have contained windows to allow air to flow in and fan the fire. The net surrounded this area to reinforce the structure without obstructing the breeze. This structural view aligns with the idea that the hollow center of the altar was filled with stones [קאסוטו], which contrasts with the perspective that it was packed with earth [רש״י, שפתי חכמים].

The net extended exactly to the midpoint of the altar, serving a profound ritual function. It acted as a highly visible boundary, separating the sacrificial blood that had to be applied to the upper half of the altar from the blood required on the lower half [רשב״ם, רש״י, תורה תמימה, ביאור יש״ר]. This strict division of blood applications was a requirement only in deeply sacred communal spaces like the Tabernacle, rather than on private individual altars [תורה תמימה]. Generations later, in the permanent Temple, this physical copper net was replaced by a red line painted around the middle of the altar, which served the exact same dividing purpose [רש״י, תורה תמימה].

To access the upper portion of the altar and perform the service above the dividing line of the net, the priests did not climb stairs. Instead, they ascended a smooth, sloping ramp positioned on the southern side. In a remarkable display of precision, this ramp did not actually lean against the altar; it stopped a mere hair's breadth away, ensuring the structures remained entirely distinct [רש״י, ביאור יש״ר].