The apostle we usually refer to as Bartholomew is also Nathanaël. Bartholomew is a patronymic, ‘bar’ is son, similar to the scot ‘Mac’ or the irish ‘O’. A full name might be Nathanaël son of Tolmai of Cana. He was a friend of Philip, whom brought him to Jesus:
Philip findeth Nathanael, and saith to him: We have found him of whom Moses in the law, and the prophets did write, Jesus the son of Joseph of Nazareth. And Nathanael said to him: Can any thing of good come from Nazareth? Philip saith to him: Come and see. Jesus saw Nathanael coming to him: and he saith of him: Behold an Israelite indeed, in whom there is no guile. Nathanael saith to him: Whence knowest thou me? Jesus answered, and said to him: Before that Philip called thee, when thou wast under the fig tree, I saw thee. — John i. 45-48.Ribera has Bartholomew, about to be raised, on the cross. He was both flayed and crucified. Michelangelo was heavily criticised, in some clerical circles, over his fresco, The Last Judgment. In this depiction of Saint Bartholomew, Bart holds a flaying knife in one hand, and his skin in another. In religious iconography, it is common for a martyr to hold, or to be pictured with the implements of their martyrdom. The skin, he is holding, is not his own. There is no beard, and the face is the painter’s.