When men a dangerous disease did 'scape
Of old they gave a cock to Aesculape
Let me give two, that doubly am got free
From my disease's danger, and from thee.
Ben Jonson (1753?-1637) from Epigrams and Epitaphs (London: Faber and Faber, 1977), p. 27.
At the very end of the Phaedo, having drunk the hemlock, Socrates is reported by Plato as saying to Crito, "I owe a cock to Asclepius; do not forget to pay it." (tr. F. J. Church) Asclepius is the Greek god of healing. Presumably, Socrates wanted to thank the god for his recovery from the sickness of life itself.
Nietzsche comments at the the beginning of "The Problem of Socrates" in The Twilight of the Idols:
Concerning life, the wisest men of all ages have judged alike: it is no good. Always and everywhere one has heard the same sound from their mouths -- a sound full of doubt, full of melancholy, full of weariness of life, full of resistance to life. Even Socrates said, as he died: "To live -- that means to be sick a long time: I owe Asclepius the Savior a rooster." (tr. W. Kaufmann)