יחזקאל, פרק מ״ג, פסוק ט״ז

The very top of the altar, the sacred space where the fire burned and sacrifices were offered, was built with precise geometric proportions. This highest section is given a unique name that reflects a profound divine phenomenon. A heavenly fire descended and rested upon the altar, taking the striking form of a lion consuming the offerings [מלבי״ם].

Although the measurements are given as twelve by twelve, the primary approach among commentators is that this does not represent the altar's total edge-to-edge size. Instead, it defines the specific inner area where the wood was arranged and the sacrifices were burned. The measurement is calculated from the exact center point outward, extending twelve cubits in every direction. As a result, the actual total surface area of the burning space was twenty-four by twenty-four cubits.

This specific dimension of the inner space is reached only after subtracting the outer perimeter of the altar. The outer edges included the raised horns at the corners and the dedicated walking path used by the priests, both of which naturally reduced the available internal area. Ultimately, the structure was perfectly square, standing entirely symmetrical and equal across all four of its sides.