In the times of Harod, Zacariah and his wife Elizabeth were believers but, weren't able to have a child because Elizabeth couldn't have a baby, and they were very old.
Zecharia isn't convinced
Then Zecharia got a job as a priest serving God, and was able to go to the temple and burn the incense.
The birth of Jesus Foretold
Then an angle came named Gabriel. The angle said, "Do not be afraid God has heard your prayer." Then he says the Lord is giving them a son, and he will be called John, and will have the Holy Spirit even before he is born.
John is born
When Gabriel tells this to Zecharia he isn't sure, because he and his wife are very old. Then the angel said he was sent from the lord. Then the angel says he will not be able to speak until this day, because he didn't believe him.
When Elizabeth was 6 months pregnant Gabriel also went to Mary who was a virgin and told her she was carrying the Messiah. After this Mary visits Elizabeth, and when Mary greats Elizabeth her baby leaped in her womb.
When it was time for Elizabeth to have the baby all her relatives and neighbors came too see her. Then everybody asked how the baby was going to be called and she said "John." Nobody thought the baby was going to be called John so the asked Zecharia. He wrote John, and he was able to speak again.