The inscription on the stone slab refers to a passage in the the Old Testament (1 Kings) which describes how after prophesying a drought Elijah was instructed to hide himself by the brook of Cherith, from which he could drink and where ravens would bring him bread and meat. Guercino painted the picture in Ferrara for his patron, Cardinal Jacopo Serra, Papal Legate of Ferrara.
During this period Guercino typically gave massiveness to his subjects by making them occupy a high proportion of the picture space. Elijah is over life-size and dominates the picture. The light cuts across the massive forms, breaking them up into patches of light and dark.