From LAUGHaDAY , the author is not known. I would wager the tale is older than I am, however.

A couple of marines were serving in Italy during the Second World War, when they came across a dead donkey. As it was starting to smell pretty bad they started digging a hole in which to bury it. But they soon got into an argument over what it was called.

The first marine said, “It’s a donkey.”

The second marine said, “No it’s a mule.”

Just then a Padre came along so they asked him to settle the argument – Is it a donkey or a mule?

“Well,” said the padre, “according to the Bible it’s an ass.”

Just then a WAC came by and asked, “What are you guys digging? A foxhole?”

The first marine said, “Not according to the Bible!”