Die Meistersinger von Nürnberg
If Walther is to win the contest he will have to compose his own mastersong and sing it.  He will have to compose it according to a lot of strict rules (the number of lines, the rhyming patterns etc.).  When he meets the other Mastersingers he introduces himself, saying that he learned the art of singing from the ancient poet Walther von der Vogelweide and from nature itself.  He sings this in a song which is very beautiful, but it does not obey the rules of the Mastersingers.  The Mastersingers are not able to understand the beauty of his song.