In the Old Testament multiple witnesses were required to establish the facts of a case. As God the Son was coming into the world in fulfillment of the Old Covenant he was accompanied by witnesses. The first was John, sent from God as had been prophesied.
John 1:6-8 There was a man sent from God, whose name was John. (7) He came as a witness, to bear witness about the light, that all might believe through him. (8) He was not the light, but came to bear witness about the light.
Mar 1:2-3 As it is written in Isaiah the prophet, “Behold, I send my messenger before your face, who will prepare your way, (3) the voice of one crying in the wilderness: ‘Prepare the way of the Lord, make his paths straight,’”
John’s own coming was miraculously proclaimed by an angel and he was a miraculous pregnancy given to his parents in their old age.
Luk 1:5-25 In the days of Herod, king of Judea, there was a priest named Zechariah, of the division of Abijah. And he had a wife from the daughters of Aaron, and her name was Elizabeth. (6) And they were both righteous before God, walking blamelessly in all the commandments and statutes of the Lord. (7) But they had no child, because Elizabeth was barren, and both were advanced in years. (8) Now while he was serving as priest before God when his division was on duty, (9) according to the custom of the priesthood, he was chosen by lot to enter the temple of the Lord and burn incense. (10) And the whole multitude of the people were praying outside at the hour of incense. (11) And there appeared to him an angel of the Lord standing on the right side of the altar of incense. (12) And Zechariah was troubled when he saw him, and fear fell upon him. (13) But the angel said to him, “Do not be afraid, Zechariah, for your prayer has been heard, and your wife Elizabeth will bear you a son, and you shall call his name John. (14) And you will have joy and gladness, and many will rejoice at his birth, (15) for he will be great before the Lord. And he must not drink wine or strong drink, and he will be filled with the Holy Spirit, even from his mother’s womb. (16) And he will turn many of the children of Israel to the Lord their God, (17) and 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 for the Lord a people prepared.” (18) And Zechariah said to the angel, “How shall I know this? For I am an old man, and my wife is advanced in years.” (19) And the angel answered him, “I am Gabriel. I stand in the presence of God, and I was sent to speak to you and to bring you this good news. (20) And behold, you will be silent and unable to speak until the day that these things take place, because you did not believe my words, which will be fulfilled in their time.” (21) And the people were waiting for Zechariah, and they were wondering at his delay in the temple. (22) And when he came out, he was unable to speak to them, and they realized that he had seen a vision in the temple. And he kept making signs to them and remained mute. (23) And when his time of service was ended, he went to his home. (24) After these days his wife Elizabeth conceived, and for five months she kept herself hidden, saying, (25) “Thus the Lord has done for me in the days when he looked on me, to take away my reproach among people.”
John’s parents were both of priestly heritage. He would serve as prophet from priestly pedigree. As His father Zechariah was serving in the temple Gabriel the angel appeared to him and announced the coming birth of his son. Gabriel said “your prayers have been answered.” This is incredible. I have to think these are prayers that were prayed many years earlier. It has likely been a long time since Zechariah asked God to fill the womb of his wife with a child. But these prayers are remembered, they are heard, they are answered.
The correct response for Zechariah would be praise and worship of God. But since he used his voice to express doubt instead of praise, he lost the use of his voice for a time. When it was returned to him at the birth of his son, he would break forth in worship and prayerful song.
Oh, lift your voice to the Lord. Even when the answer is long delayed, know that he remembers the prayers of his people rise to him like the incense in the temple. And when he does respond, open your mouth for the reason it was created and give him great praise and glory and worship.
