Knife Theory by John Stu

I was re-watching some older episodes from season 4 and 5 and came across an interesting coincidence. When Richard visits John Locke as a child back in the 40's or 50's, He brings several items with him that he claimed used to belong to John. The knife that John selects as the item that he used to own, sets Richard into a rage, and he storms off upset. In the season 5 finale the incident, I noticed that the same knife young Locke recognized as his own, is the knife Ben uses to slay Jacob. Coincidence, I think not. The show is to well written for this to be just a coincidence.

I believe Richard was upset, because he knew that knife would eventually kill Jacob (his Boy). He, along with everyone else, is trying to change the future. Only certain people can alter the future maybe.