Mark 10:38-40

But Jesus said to them, “You do not know what you are asking. Are you able to drink the cup that I drink, or to be baptized with the baptism [of suffering and death] with which I am baptized?” And they replied to Him, “We are able.” Jesus told them, “The cup that I drink you will drink, and you will be baptized with the baptism with which I am baptized. But to sit on My right or left, this is not Mine to give; but it is for those for whom it has been prepared [by My Father].”