In September Van Gogh worked on Wheat Field behind Saint-Paul Hospital with a Reaper. Intending to paint a pure sulfur yellow, he wrote to Émile Bernard that he had taken up the "devil of a question of yellow". He explained to his brother Theo, "I see in this reaper – an undefined figure, struggling in the intense heat like the devil to finish his work – I see him as an image of death in the sense that the humans are the corn that is being cut down.