If you were raised as one of Jehovah's Witnesses or had no religious education outside of the Watchtower religion, what I say now will likely shock you. I've even had people who had given up on all they learned as a JW years ago fight me on this when they first heard it (some psychological response for a few in the process of learning TTAT, apparently), but here goes...
The Messiah is a post-Biblical concept composed mostly of Jewish religious tradition, and there are no Scripture texts in the Jewish Bible (the Tanakh or "Old Testament" ) that explicitly predict, foretell or directly describe any concept connected with this Jewish concept.
(From experience, this is where JWs and even a few ex-JWs lose it and start arguing with me. But wait, it gets "worse.")
With this, Christendom agrees.
For example, the Pontifical Biblical Commission in 2001, when discussing how the Jewish Scriptures are to be interpreted by Christians stated: "Jesus in not confined to playing an already fixed role--that of Messiah--but he confers, on the notions of Messiah and salvation, a fullness which could not have been imagined in advance....It would be wrong to consider the prophecies of the Old Testament as some kind of photographic anticipations of future events....The messiahship of Jesus has a meaning [to Christianity] that is new and original." --The Jewish People and their Sacred Scriptures in the Christian Bible, II, 5, the Pontifical Biblical Commission, 2001.
(Hold on, as your jaw will remain where it is on the floor for just a little longer.)
Not a single text formally or informally held by Christians and even Jews as being "messianic" says anything about the Messiah fulfilling them.
For instance, from Christianity and Judaism:
1. That the Promised Messiah will be a descendant of King David is found in no Scripture. There are no texts in the Old Testament which speak of or have the wording describing "the Promised Messiah," let alone which say that this figure will be David's son. There are promises that David will have descendants on his throne forever, but nothing more.
2. Micah 5:2 does not say "the Messiah will be born in Bethlehem," but that merely "a ruler" representing God will come from there.
3. Zephaniah 9:9 only describes how kings of Israel would ride on donkeys up to their throne on inauguration day, not that only the Promised Messiah would use this as a unique sign (which it was not, merely the common Davidic practice).
4. Zechariah 11:11 doesn't say that the Messiah or any king would be betrayed for 30 pieces of silver.
5. Psalm 22 never says the Promised Messiah would be mocked or that people would cast lots for the Messiah's clothing. It merely describes an unnamed individual having HAD these experiences.
6. Psalm 34:20 (21) does not predict that the Promised Messiah would have no broken bones. It only days that King David once escaped from some of his enemies without even as much as a broken bone which he attributes to divine providence.
And time would fail me and we would run out of space if I went on. Look at all the so-called prophecies of the Messiah and note how "the Messiah" is not really mentioned in any of them, regardless if it is a Christian or a Jew who claims that a text foretells the Messianic figure.
And still, we are not finished!
The New Testament "fulfillments," as stated in that document from the Vatican, are mostly describing this transcendent Messiah that Jesus comes as, not one recognized or accepted by his own people. The type of fulfillment Jesus' messiahship has of the Scriptures is one which transcends their original intent, like that of Isaiah 7:14.
Whereas Isaiah 7:14 states that the child born to a young woman would be named "Immanuel" as a sign that God is with his people, in Matthew the author is saying that something far greater than a literal reading is happening in the case of Jesus.
St. Athanasius stated that "the Son of God became man so that we might become God." I know, I know. Years of JW training make you want to debate this. As a Jew I have no part in advocating the notion, but the truth of Christianity is that they believe God came in the person of Jesus of Nazareth, that God became incarnate so that mankind might share in God's divinity, "that...you might come to share in the divine nature." (2 Peter 1:4) Only the incarnation of a god would make sense in regarding such an offer of sharing "divine nature." A merely perfect man could never do so.
So, yes, though my people don't believe it (and it is the reason most of us don't), Jesus messiahship is all about Jesus being God. Sorry to rain on the parade of all those endless debates, but even we Jews know that this is not only the central claim of what it means to practice Christianity but central to all Jesus taught, said and did. If the whole "Jesus is God" thing wasn't a factor, more Jews would likely be Christians. This whole "Jesus is the Messiah" is a concept that transcends not merely the Jewish traditions about the Messiah but the Scriptures themselves.
So when Isaiah talked about the child being Immanuel, the transcendent fulfillment is that the Messiah Jesus is a literal "God With Us" experience, not merely a name for a baby.
There you go. And please, no "debate with David Jay" about the Trinity. Jews don't believe in or condone the Trinity doctrine, so this is not what I've been saying.
But what I am saying is that JW theology on Jesus does not work due to its demand for literal interpretation. There are no literal texts about the Messiah in Scripture, and as Christendom teaches, the entire Jesus thing is about God fulfilling even these traditional comcepts in a transcendent manner.