Why did circumcision take place the eighth day from birth? If birth corresponds to creation as represented by the child being brought forth into light from the dark, primordial welter and waste of the womb (acknowledgements to Robert Alter for my now-standard designation of without form and void), it seems that circumcision actually corresponds to the Resurrection of Christ as the eighth day rather than, as one might expect, the day of Passion, the day of cutting by scourges, the day of bloodshed. This should tell us things about the Resurrection.
But this correspondence seems so numerically obvious that I’m sure someone else has written on these things. Any takers?