“ In that case, remove the ‘Ashteroth Karnayim’ and there will remain the shade of the Sukkah, but here, remove the walls, and you have no shade of a Sukkah.20 Raba replied: [It is derived] from the following verse, Ye shall dwell in booths seven days,21 the Torah declared, For the whole seven days leave thy permanent abode and dwell in a temporary abode. [With a booth] up to twenty cubits [high] a man makes his abode a temporary one ”