Where music thundered let the mind be still,
Where the will triumphed let there be no will,
What light revealed, now let the dark fulfill.

May Sarton (1912–1995) Belgian-American poet, novelist, memoirist [pen name of Eleanore Marie Sarton]

“Now Voyager”
    (Source)

First published in The Lion and the Rose, Part 3 (1948).