Mark 10:38
You don't know what you are asking, Jesus said. Can you drink the cup I drink or be baptized with the baptism I am baptized with? — the cup (the cup of suffering, Psalm 75:8, Isaiah 51:17) and the baptism (of suffering and death, not the Jordan baptism) are the path to the glory James and John are requesting. You don't know what you are asking — their ignorance is genuine. The cup and baptism metaphors point to the passion — the question is whether they can share what Jesus is about to undergo.