A lot of people have discussed a particular aspect of Harry's victory over Voldemort at the end of Deathly Hallows, that in fact Harry didn't destroy Voldemort, rather Voldemort killed himself, with a curse that rebounded on him when it collided with Harry's curse. I've written previously (here) that I actually don't like this aspect of the story, since I think that Harry should have killed Voldemort directly, but as I write below, there's a definite analogue to this in the Torah.
In fact, we see throughout the Harry Potter stories that Harry's defeats of Voldemort are most often because of something that Voldemort himself did. When Harry was a baby he defeated Voldemort because of Voldemort's having killed Harry's mother unnecessarily. The same enabled Harry to defeat Quirrel (posessed by Voldemort) at the end of Sorcerer's Stone. Harry beats Voldemort at the end of Goblet of Fire because of Voldemort's wand. He escapes Voldemort at the end of Order of the Phoenix because of Voldemort's damaged soul. Over and over, Harry defeats Voldemort because Voldemort's own actions turn against him.
This is a theme that we see throughout the Torah as well. Jewish salvation is very often enabled specifically by the things that our enemies themselves do.
In the Passover story, we know that Moses was raised in Pharoh's house, as Pharoh's son. The plagues are each brought as a consequence of Pharoh's actions as well. In the Purim story, Haman's downfall is due to Esther's position as queen, which was a result of Haman and the King's immoral process of choosing a new queen.
This is even hinted in the Passover Hagadah, in the song "ve'hee she'amda." We say "This (G-d's pact with Abraham) supports us forever, because not only once but in every generation someone stands up against us (the Jews) to destroy us, but G-d always saves us from their hands." The phrase "from their hands," in Hebrew "mi-yadam" (מידם), hints to us that G-d's salvation always utilizes our enemies "hands" in bringing about our salvation - G-d always saves us through our enemies hands.
Besides learning about the nature of Divine salvation, that it seems to operate similar to Voldemort's rebounding curses, we can see a new perspective on things that others do to us. Not only do we know that G-d will always save us, we can look at things that our enemies do as the potential sources of our future Divine salvation.
I'd like to wish everyone a happy and meaningful Passover, both the seder and the holiday itself.