Then who else ?
I'm just going to look at a few of the prophecies concerning the coming Messiah.
Turn your Bibles to ... (you mean you haven't got one? You're either lazy, broke or you trust me implicitly!) ... Genesis 12:3, Genesis 18:18, Genesis 22;18, Genesis 26:4, Genesis 28:14 ... etc, etc.
You don't have to read them all, it's the same theme, repeated again and again. The theme is that of a descendant of Abraham, Isaac and Jacob who will bless the whole world.
So the Messiah is going to be Jewish. Pretty obvious really, you can't really expect the Jews to write about and have expectations of a saviour who doesn't even go to shul or speak Hebrew!
Further confirmation is given in Genesis 49:10, which identifies the Messiah as coming from the tribe of Judah (where the name Jew comes from), then 1 Chronicles 17:11-14, which further narrows things down and states that this Messiah will be descended from King David. This last scripture is worth repeating, if only for dramatic effect : "When your days are over and you go to be with your fathers, I will raise up your offspring to succeed you, one of your own sons, and I will establish his kingdom. He is the one who will build a house for me, and I will establish his throne forever. I will be his father, and he will be my son. I will never take my love away from him, as I took it away from your predecessor. I will set him over my house and my kingdom forever; his throne will be established forever. "
This is obviously not referring to his son, even though Solomon (the one with the wisdom and the wives) does fit the first part of this prophecy. Solomon died at a ripe old age, he's certainly not still reigning, as this prophecy implies!