Samsung SCH-A930

How can someone save/pull this information off the phone and save it as it was (sent or received).Being able to prove where it came from and where you sent the message. The question really is about being able to save this information ( THE CONTENT OF ) in case you ever need to prove WHAT was sent or received. I know you can get the ,sent to, and ,from, off their website (VERIZON) but it does not prove the content. I know you can save it on the phone by locking the message. But you can only hold so many messages and if you ever lose the phone or damage the phone you will lose the information.