Why we're sure that Snape is Evil

[zgirnius]

No: HPFGUIDX 153844

chrustoxos:
> 9. Therefore, somewhere towards the end of Book 7, Harry meets 
Snape - a man evil and 
> unrepented, and a man Harry has a billion reasons to hate - and, 
instead of killing him 
> straightforward, he forgives him, and thus vanquish him
> 
> 10. Snape thus a) goes to prison, b) escpaes, c) is killed by 
someone else, d) kills himself
> 
> 11. Harry has understood the full power of love, and can now meet 
LV fearless

zgirnius:
I like it as an outline of Snape's role as a preliminary 
task/obstacle for Harry in Book 7 which will help to prepare him for 
the 'main event'. But I still think Snape is 'good'.

I don't think there was a long-laid plan that Snape was to kill 
Dumbledore that night; instead, I think he and Dumbledore were 
totally taken by surprise by the success of Draco's cabinet plan. 
Nonetheless Snape was acting in accordance with Dumbledore's wishes.

But, because there was no plan, Dumbledore has not left behind any 
incontrovertible evidence to clear Snape. So, Harry will have to 
forgive/believe Snape without 'proof', making it, for Harry, quite 
the difficult task. Also, even if Snape is not guilty of being a 
traitor/loyal Voldemort supporter, he and Harry have that poisonous 
personal history which would additionally complicate matters for 
Harry.

This way we get to have our cake and eat it too: Snape does have the 
redemptive pattern (redemption being a Christian theme as well, like 
you say), and at the same time, Harry forgives him based purely on 
principle/faith, not reason/evidence.