You must have a PhD in Bovine Scatology to attempt to pull that one off. Jews missed it for the same reason you did, they didn't pay attention, that is, excluding the Messianic Jews who know you're wrong. The very day of His appearing was prophesied. No way were they not about Jesus.
We could spend pages and pages going through each of the Old Testament prophecies relied upon by Christians, but that would take this discussion way off topic and be an enormous time drain. Instead, I'll just provide one example, which I think is representative of the problem. Let's begin at the beginning of the first gospel appearing in the New Testament, Matthew.
Matthew begins his tale with Mary and Joseph. Immediately after their marriage, but somehow before they can consummate their vows, Mary becomes pregnant. Joseph is understandably troubled, but is assured by an angel that Mary remains a virgin; her child was conceived by the Holy Spirit. Matthew claims this is the fulfillment of a “prophecy” found in Isaiah 7:14 (“Therefore, the Lord himself will give you a sign: behold, a
young woman / virgin shall conceive, and bear a son, and shall call his name Immanuel.”)
There are several reasons to dismiss Matthew’s claim that Jesus’ birth fulfilled and Old Testament prophecy. First, no Hebrew scholar or critical scholar considers Isaiah 7:14 a messianic prophecy. It occurs in a story about King Ahaz of Judah, who is concerned that Jerusalem will soon be conquered. The prophet Isaiah promises Ahaz that God will destroy his enemies before a child named Immanuel (“God-with-us”), not yet conceived, reaches the age of reason. The point of mentioning the child is to establish the immediacy by which the destruction will commence. It is a secondary prophecy supporting a primary prophecy. Both prophecies come to pass, as Ahaz’s enemies are destroyed and disaster is averted. The Immanuel prophecy is made and fulfilled within the same story, leaving nothing for Jesus or anyone else to fulfill.
The second point is that while the original Hebrew word used in Isaiah 7:14, “almah,” simply meant “young woman,” this word was subsequently translated into the Greek word “parthenos” in compiling the Septuagint. While “almah” does not imply virginity, “parthenos” does. The translator of the Septuagint therefore changed the meaning of the word, resulting in a natural occurrence being transformed into a miraculous one. It is clear that Matthew used the Septuagint as a source, and thus read Isaiah 7:14 as referencing a
virgin birth when no such virgin birth was originally intended. Matthew surely would have recognized that virgin births were seen by many pagan religions as signs of divinity, noting that this would provide a great selling point for Christian missionaries.
Assume the original text of a document identified the birth of a three-legged goat as a portentous sign. Assume further that in translating that text into another language, “three-legged goat” somehow became “talking cow.” Finally, assume that a later writer supported his claims by representing that the sign was fulfilled, through the birth of a talking cow. You would no doubt dismiss his claim because (1) talking cows don’t exist in nature; and (2) the original text said nothing about a talking cow.
Matthew mis-identified scriptural authority for a virgin birth and shoehorned it into a prophecy that was never intended as messianic by its author. He then worked such a virgin birth into his nativity narrative specifically to demonstrate that such a prophecy had been fulfilled and that Jesus was indeed divine. For people willing to accept Matthew’s claims regarding the OT prophecy and buy into his narrative, this must have seemed like powerful confirmation. Once one recognizes how Matthew misrepresented the original prophecy, however, his story of an actual virgin birth is easily dismissed.