Zechariah was a priest, and the father of John the Baptist. He and his wife were very old and unable to have children. Then one day the angel Gabriel visits Zechariah to tell him that God has chosen his family to fulfill the final promise of the Old testament, that they would give birth the the "prophet of the power of Elijah" who would declare and pave the way for the Messiah. Because of his doubts, Zechariah was made mute (and possibly deaf as well) until the birth of his son. When Zechariah names him John, his tongue is released, and the response is praise and thanksgiving in the form of Zechariah's Song.