James, brother of John, was one of the Apostles closest to Christ. He was present at the Transfiguration and at the Agony in the Garden. He was tried in Jerusalem because of his faith and executed in the year 44. According to later embellishments of the story of his life he went on a mission to Spain, where he is thought to be buried at Compostela, the city which became the major focus of his cult. James is the patron saint of Spain.
He is most often represented with a pilgrim's staff and broad-brimmed hat, as well as a gourd for carrying water and a scallop shell. The shell is worn by pilgrims to Compostela; see, for example, that worn by the figure in Caravaggio's 'Supper at Emmaus' in the Collection.