Chalice and Serpent
 

There are at least two interpretations of this symbol.  The first is that it represents the Apostle John, having been told by Jesus that he would drink from his cup, indicating that the apostle’s life would not be an easy one.  Another interpretation is based on John 3:14-15: “And just as Moses lifted up the serpent in the wilderness, so must the Son of Man be lifted up, that whoever believes in him may have eternal life.”