Life’s race well run,
Life’s work well done,
Life’s crown well won,
Now comes rest.Edward H. Parker (1823–1896) American physician, poet
Epitaph of President James Garfield (1881)
(Source)
The phrase was engraved on a tablet placed at the head of his coffin while he lay in state at Cleveland's Memorial Park.
The passage was selected by a committee without a clear source of the material, but it appears to be a loose transcription of the first stanza of a poem Parker wrote for his mother-in-law's funeral:Life's race well run,
Life's work all done,
Life's victory won,
Now cometh rest.
The differences may be because the Garfield epitaph was back-translated from a Latin translation of Parker's original.
Much more discussion here.

