The image is of the painting SAINT GEORGE AND THE DRAGON (c. 1470) by Paolo Uccello. Oil on canvas.
My parents had a print of this hanging in the dining room of the house we lived in for eighteen months when I was seven to eight years old. The image disturbed me deeply at the time (and still does) because I thought the dragon in the picture seemed innocent and passive, undeserving of having its eye and brain gored through by the knight. At that time, I shared how upset I felt for the dragon to my then step/foster mother, who my father never married but cohabitated with for fifteen years.