LOL!

The way you determine the common, ordinary ass (arse) from an Ass like Jethro is simple. If it's Jethro, then "Ass" is capitalized, as in "Jethro the Ass". Also...your ass (your arse) is always behind you, while Jethro might be behind you (and if he is, watch out!), but he might also be in front of you, beside you, or over in the next yard.