ויקרא, פרק ז׳, פסוק ד׳

Preparing an animal for a sacrifice requires a precise separation of its internal organs and specific fat portions before they can be burned on the altar. The instructions mandate the removal of the fat resting on the flanks, or loins. Additionally, the diaphragm, which serves as an appendage on the liver, must be collected. This diaphragm is extracted together with the kidneys. The physical act of removal is highly deliberate; these specific elements are detached and taken away from the liver, because the main body of the liver itself is not intended to be burned as part of the offering [ביאור שטיינזלץ].