Luke 1:5-20

5 There was in the days of Herod, the king of Judea, a certain priest named Zacharias, of the priestly division of Abijah. He had a wife of the daughters of Aaron, and her name was Elizabeth.  6 They were both righteous before God, walking blamelessly in all the commandments and ordinances of the Lord.  7 But they had no child, because Elizabeth was barren, and they both were well advanced in years.  8 Now it happened, while he executed the priest's office before God in the order of his division,  9 according to the custom of the priest's office, his lot was to enter into the temple of the Lord and burn incense.  10 The whole multitude of the people were praying outside at the hour of incense.

11 An angel of the Lord appeared to him, standing on the right side of the altar of incense.  12 Zacharias was troubled when he saw him, and fear fell upon him.  13 But the angel said to him, "Don't be afraid, Zacharias, because your request has been heard, and your wife, Elizabeth, will bear you a son, and you shall call his name John.  14 You will have joy and gladness; and many will rejoice at his birth.  15 For he will be great in the sight of the Lord, and he will drink no wine nor strong drink. He will be filled with the Holy Spirit, even from his mother's womb.  16 He will turn many of the children of Israel to the Lord, their God.  17 He will go before him in the spirit and power of Elijah, 'to turn the hearts of the fathers to the children,' and the disobedient to the wisdom of the just; to make ready a people prepared for the Lord."

18 Zacharias said to the angel, "How can I be sure of this? For I am an old man, and my wife is well advanced in years."

19 The angel answered him, "I am Gabriel, who stands in the presence of God. I was sent to speak to you, and to bring you this good news.  20 Behold, you will be silent and not able to speak, until the day that these things will happen, because you didn't believe my words, which will be fulfilled in their proper time."

Hebrews 11:6

6 Without faith it is impossible to be well pleasing to him, for he who comes to God must believe that he exists, and that he is a rewarder of those who seek him.