Although, the difference between a sexton and a grave digger must also be taken into account. A sexton oversees many different jobs around the church and surrounding areas. A grave digger simply digs graves. There are sextons who also dig graves and some that do not. It is completely possible that the Gravedigger has been a sexton for 30 years, but has not been digging graves for that entire time. This could be another example of the character's very round-about way of speaking.