Lyric discussion by Volponi 

Everyone gets this one wrong. Johnny lost his soul. In the very first verse, the song tells us that the devil was "looking for a soul to steal". Not "a soul to win fairly in a fiddling contest", a soul to STEAL. Of course the devil isn't exactly the honorable sort and shouldn't be expected to honor a bargain anyway. He's spent thousands of years perfecting the art of tricking men. He offers Johnny a deal. The "deal" is crafted such that it appeals to johnny's pride (one of the 7 deadly sins), and dangles a golden fiddle before Johnny to appeal to his greed (another deadly sin) in case his pride wasn't enough. Johnny acknowledges that "it might be a sin" before issuing the brash, prideful statement "I'm the best there's ever been" and accepts the deal. Sure, Johnny wins the fiddling contest, but the contest was never the devil's true interest. The devil lost on purpose, just to further inflate Johnny's pride. The devil's true interest was to STEAL Johnny's soul by tricking Johnny into agreeing to the deal at all, and our poor Johnny's soul was doomed from the moment he fell into the devil's trap and accepted the deal.

Although, the devil is 'way behind', and 'willing to make a deal'.

@Volponi I always interpreted the "sin" was participating in betting. \r\n\r\nThe sin of pride drew him into the sin of gambling. \r\n\r\nOne sin begets another.

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