Many thanks to @johnbrady for calling this to my attention in a comment on my earlier post
Edna St. Vincent Millay
I shall die, but
that is all that I shall do for Death.
I hear him leading his horse out of the stall;
I hear the clatter on the barn-floor.
He is in haste; he has business in Cuba,
business in the Balkans, many calls to make this morning.
But I will not hold the bridle
while he clinches the girth.
And he may mount by himself:
I will not give him a leg up.
Though he flick my shoulders with his whip,
I will not tell him which way the fox ran.
With his hoof on my breast, I will not tell him where
the black boy hides in the swamp.
I shall die, but that is all that I shall do for Death;
I am not on his pay-roll.
I will not tell him the whereabout of my friends
nor of my enemies either.
Though he promise me much,
I will not map him the route to any man’s door.
Am I a spy in the land of the living,
that I should deliver men to Death?
Brother, the password and the plans of our city
are safe with me; never through me
Shall you be overcome.