Or, those who guard the Yod י (=10), which is the sign of the covenant of circumcision, which is for the ‘eight’ days, for all is 18∞ḥaiy.
Or, those who lay phylacteries (tephilin) every day, which are the letter Yod י, as it says: (Ex. 13:16) And it shall be for a sign... etc. and they bind them with the 8 ‘housings’ of the phylacteries, which are the 4 housings of the tephilin (phylacteries) of the head, and the 4 scrolls of the tephilin of the hand.
Or, those who preserve the letter Yod י, the Sabbath, in its domain, which is 8 – two thousand cubits in each direction – and all is 18.