How to block a number but save the messages?

I have a iPhone 4 with the new iOS7 update. I know there's a blocking service on the new update, but I want to block this individual and store the messages so I can view them when I unblock the number. Is there any way to do that via the iOS7 update or by an app?

I don't know, but you could always screenshot them. That may be the only way to save the messages. However, I don't know what blocking a number entails - it might just prevent future messages, but save the previous ones. If you really want to keep the messages, though, I wouldn't risk it - I would just screenshot them.