||He shall present the choicest parts of his peace offering as a fire offering to God, removing the broad tail up to the backbone, along with the layer of fat covering the stomachs and all the other fat attached to the stomachs.
Vehikriv mizevach hashlamim isheh l'Adonay chelbo ha'alyah tmimah le'umat he'atseh yesirenah ve'et-hachelev hamechaseh et-hakerev ve'et kol-hachelev asher al-hakerev.
(Rashi; Targum Yonathan; Yad, Maakhaloth 7:5; cf. Ramban). See Genesis 4:4. Or, 'the fat broad tail' (Ibn Ezra), or 'the fat and broad tail' (Saadia). See Exodus 29:22.
Atzeh or etzah in Hebrew. The bone over the kidney (Chullin 11a; Rashi; Saadia; Ibn Janach; Radak, Sherashim; Yad, Maaseh HaKorbanoth 1:8; Yoreh Deah 64:13 in Hagah). This is usually identified as the os cruris or the os caudae coccygisve.