I heard this years ago so I have to paraphrase it from memory so if anyone knows the joke correctly please correct me, but my version has the gist.

A well known scientist at a major university was thoroughly convinced that with today's technology there was no longer a need for God. With science we can do all of these things ourselves. Unfortunately, the professor passed away before he could finish his experiments. After passing, he was sent to heaven to meet God personally, when God asked him about his theory he said "yes God with today's technology we can do anything that you can do". So God decided to put him to a test. God says' "OK professor I will perform a miracle first and I want you to do the same thing". "Fair enough" the professor says'. God then picks up a handful of dirt, throws it into the air and a beautiful castle forms in front of their eyes. The professor chuckles and says I can do that and as he bends down to pick up the handful of dirt God stops him and says "Professor,use your OWN dirt". Ben

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