The painting shows Paul during his incarceration. He sits on a bench, lost in meditation, his meagre belongings by his side. Despite the realistic composition of figure and scenery, every element has a narrative and symbolic function. The large sword clearly alludes to his impending martyrdom, yet in combination with the books it also exemplifies Paul's missionary practice of harnessing word and deed. The diffuse light surrounding the saint like a halo casts a shadow of the window grille and highlights the saint's imprisonment. This subtle pictorial language permits Rembrandt to visualise history without going into actual events.