User blog comment:FairyRaven/Fairy Tail Chapter 368: The Third Seal, Review and Commentary/@comment-4829046-20140125070131/@comment-4829046-20140125171718

Well I have my own stand-alone theory but I prefer it if he knew Natsu because of Zeref's connection with him. If this has something to do with Natsu's 400-year theory, then Silver might have even known him back then. So many probables and yet it feels that they won't hit the mark...