Random Internet Idiot

“Avada Kedavra!” Harry said, pointing his wand at Ron. “HARRY, NO!” Hermione screamed, but it was too late. A flash of green light shot from Harry's wand and struck Ron in the chest. Ron stood there, blinking in surprise. “Harry… what just happened?” he asked. “I figured it out,” Harry said, holstering his wand. “The Killing Curse's incantation comes from the Aramaic אַבַדָא כְּדַברָא, meaning ‘let the thing be destroyed’. I did some more research, and I think it's very likely that our wizarding ancestors once used the same incantation to cure diseases. All you have to do is desire to destroy the disease rather than the person.” He turned to Ron. “Your wizarding lice are cured now.”