Eru Iluvatar, the One Alone, created the Ainur
spirits from his thought (including the Valar of Time), kindling them
to life with the Flame Imperishable that is found within his being,
then made the three musical Themes of creation. They were Arda
Unmarred,
Arda Healed, and that which has not yet been sung.
The Ainur sang and
worked
those themes to create the physical Ardas.
Within Arda, the Children of
Iluvatar came to existence, and both Ainur and the Children learned
much.
In the future, after the Last Battle, Eru's themes
will be played
by the Ainur and the other Children of Iluvatar together with true
understanding,
and the music shall at last take perfect physical form.
Reference: Silmarillion
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