Luke's Gospel narrates that before the Annunciation to Mary, an angel appeared to a priest named Zechariah while he was serving in the Jerusalem temple, announcing that his wife Elizabeth, both of them described as elderly and previously childless, would bear a son to be named John, who would prepare the way before a coming figure of great significance. When Zechariah expresses doubt, given his and Elizabeth's age, he is struck unable to speak until the promised birth occurs, a sign later fulfilled when Elizabeth gives birth and Zechariah, asked to confirm the child's name in writing since he could not speak, writes that the boy is to be called John, at which point his speech returns.
The narrative places John's conception six months before Jesus's own conception at the Annunciation, a chronological detail Luke uses to link the two infancy narratives together explicitly, since Gabriel cites Elizabeth's advanced pregnancy to Mary as evidence that nothing is impossible with God.
John the Baptist grew, according to the Gospels, to become an ascetic preacher whose ministry of repentance and baptism in the Jordan directly preceded and, in the Gospel accounts, prepared the way for Jesus's own public ministry, a role Luke's infancy narrative establishes from before John's birth.