If there lingers the slightest doubt that Princeton Pro Musica is one of New Jersey’s chief cultural treasures, let it be laid to rest by this year’s flawless performance of Handel’s great oratorio, The Messiah. Performing this demanding musical legacy presents certain unique challenges. Among these is the simple fact that everyone has heard it many times, by many different organizations, both professional and amateur. Every classical music lover will have several recordings of it. Naturally, in such a situation, schools of thought will form regarding interpretation and style. These may be defended with passion and other interpretations derided. Hence, one may set out to walk upon a path of eggs when one decides to perform such a well-known composition.