It pays to know one's own Faith. If those around Elizabeth and Zachary knew the prophecies, they may have paid more attention to the birth of this, the greatest of prophets.
Luke 1:57-66Douay-Rheims
57 Now Elizabeth's full time of being delivered was come, and she brought forth a son.
58 And her neighbours and kinsfolks heard that the Lord had shewed his great mercy towards her, and they congratulated with her.
59 And it came to pass, that on the eighth day they came to circumcise the child, and they called him by his father's name Zachary.
60 And his mother answering, said: Not so; but he shall be called John.
61 And they said to her: There is none of thy kindred that is called by this name.
62 And they made signs to his father, how he would have him called.
63 And demanding a writing table, he wrote, saying: John is his name. And they all wondered.
64 And immediately his mouth was opened, and his tongue loosed, and he spoke, blessing God.
65 And fear came upon all their neighbours; and all these things were noised abroad over all the hill country of Judea.
66 And all they that had heard them laid them up in their heart, saying: What an one, think ye, shall this child be? For the hand of the Lord was with him.