Iconography
In traditional iconography, Peter has been shown very consistently since early Christian art as an oldish thick-set man with a "slightly combative" face and a short beard, and usually white hair, sometimes balding. He thus contrasts with Saint Paul who is bald except at the sides, with a longer beard and often black hair, and thinner in the face. One exception to this is in Anglo-Saxon art, where he typically lacks a beard. Both Peter and Paul are shown thus as early as the 4th century Catacombs of Marcellinus and Peter in Rome. Later in the Middle Ages his attribute is one or two large keys in his hand or hanging from his belt, first seen in the early 8th century. More than many medieval attributes, this continued to be depicted in the Renaissance and afterwards. By the 15th century Peter is more likely to be bald on the top of his head in the Western church, but he continues to have a good head of hair in Orthodox icons.
The depiction of Saint Peter as literally the keeper of the gates of heaven, popular with modern cartoonists (see next section) is not found in traditional religious art, but Peter usually heads groups of saints flanking God in heaven, on the right hand side (viewer's left) of God. Narrative images of Peter include several scenes from the Life of Christ where he is mentioned in the Gospels, and he is often identifiable in scenes where his presence is not specifically mentioned. Usually he stands nearest to Christ. In particular, depictions of the Arrest of Christ usually include Peter cutting off the ear of one of the soldiers. Scenes without Jesus include his distinctive martyrdom, his rescue from prison, and sometimes his trial. In the Counter-Reformation scenes of Peter hearing the cock crow for the third time became popular, as a representation of repentance and hence the Catholic sacrament of Confession or Repentance.
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