For four hundred years the Israelites had been looking for the Messiah. The four Gospels describe many people whose hearts and minds were touched to let them know the Messiah has come, even when the Savior was just an infant.
Mary, the mother of Jesus received a startling angelic announcement, and she sang a great song. She was the virgin predicted in Isaiah 7.14. Her betrothed, Joseph, had a dream (and another dream later, to help keep the baby safe) letting him know that Mary was chosen by God; she was faithful; she would be a good mom; and he should marry her. Mary’s cousin Elizabeth knew about Jesus because her own special in-utero baby, who would become John the Baptist, was jumping up and down. The Magi from the East started their journey well before the birth, following a star that led them to Jerusalem, and then learning about Bethlehem because the Jewish scholars knew Micah 5.2. Shepherds out in the field received a double angel treat – the announcer angel scared them wide awake and told them where to look for the baby, and then the whole chorus shows up to sing God’s praises. And two mostly-retired people were in the temple when the infant Jesus was brought in for circumcision. Simeon was waiting for the Lord’s Christ, and the prophetess Anna recognized that the redeemer had come.
The Holy Spirit worked in a multitude of marvelous ways – angel announcements, plus a back up choir; dreams; stars; prophecies from scripture and prophets listening; and a bouncing baby boy. All these people told their stories, remembered what happened, and treasured the events in their hearts. But the general populace did not catch on or make a big deal (except maybe Herod, who tried to have the baby killed, thus fulfilling Jeremiah 31.15) because the time for that had not yet come. The Messiah had been announced and everyone still had to wait a bit.