Luke 1:16-18

He will bring back many of the people of Israel to the Lord their God. And he will go on before the Lord, in the spirit and power of Elijah, to turn the hearts of the parents to their children and the disobedient to the wisdom of the righteous—to make ready a people prepared for the Lord.” Zechariah asked the angel, “How can I be sure of this? I am an old man and my wife is well along in years.”