O zittre nicht, mein lieber Sohn

"O zittre nicht, mein lieber Sohn" ("Oh, tremble not, my dear son") is the first aria performed by the Queen of the Night (a famous soprano coloratura part) in Mozart's singspiel The Magic Flute (Die Zauberflöte). It is not as well known as the Queen's second aria, "Der Hölle Rache kocht in meinem Herzen", though no less demanding; the aria requires a soprano coloratura with extremely high tessitura and great vocal flexibility.

The role of Queen of the Night demands a range that until Mozart's time was almost never called for, and this opened the door for later composers to call for specific kind of singers (lyric, dramatic, coloratura etc.), rather than just "soprano", "tenor" etc.

The part, in whole, includes two arias, O zittre nicht and Der Hölle Rache. The first calls for a rather lyric and flexible voice while the second requires a dramatic and powerful voice. Originally, the part was written for Josepha Hofer, the composer's sister-in-law, whose voice possessed both of these qualities. Most modern performers are specialists in either lyric or dramatic style. This, along with the difficulty of the two arias, makes the role of the Queen of the Night one of the most demanding in operatic repertoire.

In the preceding scene, Prince Tamino was shown a portrait of the Queen's daughter Pamina and fell instantly in love with her, singing of his feelings in the aria "Dies Bildnis ist bezaubernd schön". The Queen then makes a dramatic entrance, preceded by the Three Ladies calling to Tamino "Sie kommt! Sie kommt!" ("[Here] she comes!"). The grand entrance music for the Queen is in B♭, marked Allegro maestoso, with the following stage direction:

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