As his raft skimmed over the water, taking him back to the mortal world, he understood a line from the Prophecy better-an oath to keep with a final breath. He understood how dangerous oaths could be. But Leo didn't care. "I'm coming back for you, Calypso," he said to the night wind. "I swear it on the River Styx.
The greatest thing a human soul ever does in this world is to see something and tell what it saw in a plain way. Hundreds of people can talk for one who can think, but thousands can think for one who can see. To see clearly is poetry, prophecy and religion, all in one.
I have done some indiscreet things in my day, but this thing of playing myself for a prophet was the worst. Still, it had its ameliorations. A prophet doesn't have to have any brains. They are good to have, of course, for the ordinary exigencies of life, but they are no use in professional work. It is the restfulest vocation there is. When the spirit of prophecy comes upon you, you merely take your intellect and lay it off somewhere in a cool place for a rest, and unship your jaw and leave it alone; it will work itself. The result is prophecy.
Have to? Of course you have to! But only because of you, Harry, won't rest until Voldemort is finished! Think now, for once, if you have never heard of the prophecy! What would you do?