Leviticus 3:4

and the two kidneys, and the fat that is on them, which is by the flanks, attached to the muscles in the upper pelvic cavity, and the caul above the liver, the small net of adipose membrane extending from the liver to the kidneys, with the kidneys, that is, together with, or upon, the kidneys, as they lay in position, it shall he take away from the rest of the animal.