Here's something that I can't recall hearing or reading anyone mention or ponder over, about the Gospel stories of the birth of Jesus. Of course, maybe someone has brought up this point and I've missed it.
The Nativity stories appear in the books of Matthew and Luke, with different details, but making a similar point: That the birth of Jesus did not go unnoticed, and there was quite a lot of excitement attending the arrival of the Promised One.
Like almost all other biographical details of Jesus' life, the Nativity story (in its different versions) was cooked up in such a way as to appear to satisfy scriptural prophecies that had been taken as describing the life of the Christ. (In many cases there is no real indication within the context of those prophecies that the Christ is what they were actually talking about, and in some cases the purported prophecy can't be found anywhere in scripture.)
In Matthew's account, a group of wise men (many people take it that there were three of them, probably based on the fact they bestowed three different gifts on the Christ child) were alerted to the birth of a "king of the Jews" by the appearance of a new star. After a side trip to tell King Herod the great news (as if the "wise" men thought Herod would be thrilled by it -- predictably, he wasn't), the wise men followed the star until it stopped over a stable in Bethlehem, wherein Jesus lay. They celebrated a bit, gave the gifts, and returned home, avoiding returning to Herod to reveal the child's location because a dream had told them not to. (Even their dreams were smarter than they were.)
In Luke's story, a group of shepherds was alerted by a glorious angel, soon joined by more angels, to the birth of "the Savior, the Messiah, the Lord." The shepherds went to Bethlehem, saw Jesus, were thrilled, and "spread the word" to everyone about the event, all of whom were "amazed."
So according to the Nativity stories, the world knew instantly, at the time of his birth, that a "king of Jews" (says Matthew), "Messiah and Savior" (says Luke) had arrived in the world, the wise men told Herod about it (who instituted a mass killing of babies just to be safe), the shepherds told everyone they met, who all believed them, so both Matthew and Luke make a point of the huge news it was that this child had been born. Luke has the baby Jesus getting even more instant attention: when Joseph and Mary took Jesus into Jerusalem for the traditional purification rites, a man named Simeon made a big fuss over him, recognizing him at once as the savior who would do long-promised things, and then an old woman named Anna reacted similarly and (like the shepherds) began spreading the word to "all who were looking forward to the redemption of Jerusalem."
Everybody totally forgot. This incredibly important news just slipped everybody's minds, for years. At age twelve, Jesus slipped away from Mom and Dad and held forth in the temple courts in Jerusalem, interpreting scripture and answering questions, amazing everyone, and nobody remembered the kid all of that stuff had been said about, in that same temple, twelve years earlier. Nobody had kept track of him, despite all the exciting news about him that the shepherds and Anna had spread far and wide.
And then another eighteen years or so went by, and nobody seems to have recalled that incident (not even Matthew), and Jesus had to introduce himself to the world all over again (with help from John the Baptist) as a humble carpenter and itinerant teacher.
It all happened in that one tiny geographic area, a wonderful birth of an important king/savior/Messiah that was signaled by celestial fireworks and hosts of angels, and the news spread all around from various witnessing sources, and then the witnesses and the people they told all went back to herding sheep, building outhouses, growing grain, or being wise, with no memory of any of this, as an entire generation passed before Jesus began his ministry.
Obviously one can't argue that (for whatever reason) God made them all forget, because if you don't want people remembering an event, you don't start by putting on a spectacular show with trumpeting angels and a supernova in the sky.
It is all very odd.