I'm sorry, but I don't really think it's fullfilling a prophesy to purposely try to fullfill it. What I mean is, if that prophesy were true, then it would have happened whether or not Jesus commanded his disciples to buy the swords. That's like a young person trying to prophesy that he will die on his 82nd birthday, and then, on his 82nd birthday, he goes out and buys a gun to shoot himself in the head to prove to people that he could predict the future. Nothing supernatural about it.
