Plaudite, amici, comedia finita est. [Applaud, my friends, the comedy is over.]

As reported in: Beethoven, A Memoir (1876) by Elliott Graeme and Ferdinand Hiller, p. 169

The authenticity of this quote is disputed.

According to Anton Schindler (biographer of Beethoven):
Scarcely had the priest left the room before he said to me and young von Breuning, "Plaudite, amici, comœdia finita est. Did I not always say that it would end thus?"

But his close friend Anselm Hüttenbrenner wrote:
It is a pure invention that Beethoven spoke the words “Plaudite, amici! Comœdia finita est!” to me, for I was not present when the rite was administered in the forenoon of March 24, 1827. And surely Beethoven did not make to others an utterance so completely at variance with his sturdy character. But on the day of her brother-in-law’s death Frau v. Beethoven told me that after receiving the viaticum he said to the priest, "I thank you, ghostly sir! You have brought me comfort!"

As reported in: The Life of Ludwig van Beethoven (Vol. 3) By Alexander Wheelock Thayer

See also I will hear in heaven!