The saint, seated, is wearing a tunic under a thick cloak. His hair is dark, his beard tinged with grey and his face deeply lined, while a halo of light around his head proclaims his sainthood. He is holding a book as a sign that he is an apostle and perhaps also an intellectual and philosopher, although he is clearly identified by the inscription at top left : 'S. PAVLVS'. This is a painting from the artist's youth when he was still living in Seville before entering the service of the Spanish King Philip IV in Madrid. It is considered a key work for understanding the influence of Caravaggio's pictorial realism in Spain.