I think Snape knew. He's not an idiot to take an Unbreakable Vow on an issue he doesn't know. but that's not the whole of it. Let's see what he says: "If Draco succeeds," said Snape, still looking away from her, "he will be honored above all others." He said that and how many tasks would imply this? You can say that he might have deduced it from what Bella had previously said: "Draco should be proud," said Bellatrix indifferently. "The Dark Lord is granting him a great honor. And I will say this for Draco: he isn't shrinking away from his duty, he seems glad of a chance to prove himself, excited at the prospect —" But granting a great honor isn't the same as granting that he'll be honored above all others.And a little later Snape says: "He intends me to do it in the end, I think. But he is determined that Draco should try first. You see, in the unlikely event that Draco succeeds, I shall be able to remain at Hogwarts a little longer, fulfilling my useful role as spy."
A task that the Dark Lord would want Snape to do and that wouldn't allow him to remain at Hogwarts. Not many tasks would so completely make sense with what he says. I think it would be a very big bluff he he was saying those things without really knowing wht the task was. But even if he hadn't known in the beginning, by the time he made the Vow he certainly did. I knew when I first read it that it could only be killing Dumbledore or Harry. Think of what Narcissa said: "But he won't succeed!" sobbed Narcissa. "How can he, when the Dark Lord himself— ?" Snape, that is a very clever man, certainly knew that he would have to betray the Order of the Phoenix and kill either its leader or the only one with the power to defeat the Dark Lord (Snape knew at least the beginning of the prophecy).
no subject
"If Draco succeeds," said Snape, still looking away from her, "he will be honored above all others." He said that and how many tasks would imply this? You can say that he might have deduced it from what Bella had previously said:
"Draco should be proud," said Bellatrix indifferently. "The Dark Lord is granting him a great honor. And I will say this for Draco: he isn't shrinking away from his duty, he seems glad of a chance to prove himself, excited at the prospect —"
But granting a great honor isn't the same as granting that he'll be honored above all others.And a little later Snape says:
"He intends me to do it in the end, I think. But he is determined that Draco should try first. You see, in the unlikely event that Draco succeeds, I shall be able to remain at Hogwarts a little longer, fulfilling my useful role as spy."
A task that the Dark Lord would want Snape to do and that wouldn't allow him to remain at Hogwarts. Not many tasks would so completely make sense with what he says. I think it would be a very big bluff he he was saying those things without really knowing wht the task was. But even if he hadn't known in the beginning, by the time he made the Vow he certainly did. I knew when I first read it that it could only be killing Dumbledore or Harry. Think of what Narcissa said:
"But he won't succeed!" sobbed Narcissa. "How can he, when the Dark Lord himself— ?"
Snape, that is a very clever man, certainly knew that he would have to betray the Order of the Phoenix and kill either its leader or the only one with the power to defeat the Dark Lord (Snape knew at least the beginning of the prophecy).