I am not a devil worshiper :?
The pentacle or pentagram goes way back to pythagoras and the pythagoreans who studied this symbol's mathematical properties.
By drawing a pentagram right, you can derive the number phi from it, my signature 1.618. Phi being the Golden Ratio and the Divine Proportion of the human body (as well as many other living things) makes this symbol very neat.
Since this symbol contains the number of Divine Proportion, you could use this symbol for your relegion as the creator. Creating everyone equal this was his blueprint.
Hopefully I didn't go on to far, but it should be obvious now that I like the symbol becuase of it's very intreging mathematical properties.
An upside down pentacle with a goat's head in it should remind you more of Satan.
D.J.