[...] I was suddenly inspired with an idea for the orchestral prelude to the third act of The Mastersingers. In this act, the culminating point of emotion belongs to the moment at which Sachs rises before the assembled people and is received by them with an outburst of intense enthusiasm. At that point the people sing solemnly and plangently the first eight verses of Sachs's poem on Luther. The music for it was ready. Now, as prelude to the third act, in which the curtain rises on Sachs sitting deep in thought, I let the bass instruments play a faint, soft, deeply melancholy passage, expressive of utter resignation; then on horns and sonorous brass comes like a gospel the solemnly joyful melody of the "Wacht auf! Es rufet gen den Tag; / Ich hör' singen im grünen Hag / Ein' wonnigliche Nachtigall" [Awake! The dayspring draweth near; / And in the thicket green I hear / A joy-entranced nightingale], and the subject is then taken up with increasing power by the whole orchestra.
I am clear now that this is my most perfect masterpiece, and—that I am destined to complete it. [...]
Source: Letters of Richard Wagner, Vol. 2, selected and ed. Wilhelm Altmann, trans. M. M. Bozman (J. M. Dent & Sons, 1927), No. 531