Charles Baudelaire - The Warner

Every man worth the name
has a yellow snake in his soul,
seated as on a throne, saying
if he cries: ‘I want to!’: ‘No!’
Lock eyes with the fixed gaze
of Nixies or Satyresses, says
the Tooth: ‘Think of your duty!’
Make children, or plant trees,
polish verses, or marble frieze,
the Tooth says: ‘Tonight, where will you be?’
Whatever he likes to consider
there’s never a moment passing
a man can’t hear the warning
of that insufferable Viper.

Charles Baudelaire

http://www.poemhunter.com/poem/the-warner/