How will YOU know?

If this has already been brought up I appologize, but I couldn't find it in my searching. OK, prerequisite appology out of the way, onto the discusssion.

I have been doing alot of driving lately, and when I get driving my mind gets spinning out of control and I tend to get thinking about some things I rarely think about. The other day my mind setled on one and it wouldn't leave. I figured I would put it to the educated masses here and see what they thought.

All three of the "cousin" religions believe that there will come the final prophet. For the Jews it is the Messiah, for the Christians it is the second coming, for the Muslims it is the final Imam. What I am wondering is how will YOU know?

I am not interested in the scriptures. I have read them and I know what they say. What I am interested in, is what would make you personally believe that someone was "The Chosen One". I am not looking to insult anyone with this, or to "troll". I feel that this is truly where one's beliefs are tested. It is great that you can put your faith into the words that you believe have come from God (I say it like that because all 3 believe in different books), but to believe that a living person is the last prophet is the ultimate test of faith.