>>2990902i found it, in chretien de troyes story of the grail, around line 6223, when Perceval is lectured about Christianity. "This was a true holy death, which saved the living and brought the dead back to life. The wicked Jews, whom we should kill like dogs, brought harm to themselves and did us great good when in their malice they raised Him on the Cross: they damned themselves and saved us."
