St. John with Serpent in Chalice

From the Cleveland Museum of Art record

According to legend, John the Evangelist was given a cup of poisoned wine that he drank without harm. As emblems of the tale, John’s chalice symbolizes the Christian faith prevailing over death, signified by the serpent. As a print, Meckenem's representation of Saint John like a sculpture in an architectural niche made it possible for more people to personally own a religious image that they might otherwise only have seen at a church. Saint John was an especially popular saint throughout the Middle Ages and into the early modern era because his devotion to Christ set an example for all good Christians.