text: You don't understand. 
  
  Jesus re-defined priesthood...perfectly.
  
  He came to be both victim & priest; a perfectly fused offering.
  
  A priest, even in the Jewish time, "offered sacrifices".  In those days proxies were offered, as a means of restorative justice.
  
  Jesus made perfect the priesthood.  
  
  From St Matthew: “Now as they were eating, Jesus took bread, and blessed, and broke it, and gave it to the disciples and said, ‘Take, eat; this is my body.’ And he took a cup, and when he had given thanks he gave it to them, saying, ‘Drink of it, all of you;
  for this is my blood of the covenant, which is poured out for many for the forgiveness of sins. I tell you I shall not drink again of this fruit of the vine until I drink it new with you in my Father’s kingdom.”
  
  A priest's offering of self. 
  
  And this is what is meant when the Church talks about the "common priesthood" of all Christians and the "ministerial priesthood."  You and I must offer all we do; but the Mass is offered by a priest