In Luke 1, we have two intersecting pregnancy stories: Zacharias and his wife Elizabeth, followed by Mary the (eventual) mother of Jesus. Zacharias was a priest who is described with his wife Elizabeth as being "righteous in the sight of God, walking blamelessly in all the commandments and requirements of the Lord" (v. 6). However, they were childless and advanced in years.
On one particular day, when Zacharias entered the temple to perform his priestly duties, he encountered the angel Gabriel. The angel told Zacharias that Elizabeth would bear a son who would turn many people's hearts back to the Lord. But Zacharias questioned Gabriel: "How will I know this? For I am an old man and my wife is advanced in years" (v. 18). Because he questioned Gabriel, Zacharias was made mute until his wife gave birth to their son.
On the surface, this hardly seems fair for at least three reasons:
What the angel said to Zacharias is most unusual. Zacharias and Elizabeth were too old to have children. Wouldn't most of us doubt such a message if we received it?
Zacharias had lived righteously and served the Lord faithfully all of his life. Shouldn't he be given a break for being a little weak in his faith just this once?
Later in the same chapter of Luke's narrative, Mary likewise questions Gabriel when she is told of her pending miraculous pregnancy. However, unlike Zacharias, she is not punished.
I believe that there are at least three possible reasons Zacharias was made mute and yet Mary was unpunished. First, we must consider the nature of the recipients of Gabriel's message. Gabriel may have held Zacharias to a higher standard. After all, he was a priest with many years of walking with the Lord, while Mary was simply a teenager. If anyone should have been able to trust God's abilities to do miracles, it would be the well-trained and well-experienced Zacharias.
Second, the nature of the miracles to be believed was different for Zacharias and Mary. Zacharias was asked to believe something highly unlikely (an old couple having a child), while Mary was asked to believe something impossible (a virgin having a child). The angel might be patient with a person for questioning the impossible, but questioning a holy angel from heaven about something that only rises to the level of 'unlikely' shows a lack of faith from an otherwise righteous man like Zacharias. This rings especially true since Abraham and Sarah's miraculous pregnancy exists as a very prominent precedent of the Lord doing the same miracle.
Finally, and most conclusively, there seems to be a difference in the nature of the questions raised by Zacharias and Mary. After Gabriel, a holy angel of heaven, told him what would occur, Zacharias asked, "How will I know this?" I wouldn't have been surprised if Gabriel had replied, "Because I just told you! That's how you know!" Gabriel's response to Zacharias gives us an important clue as to what was really occurring in Zacharias's heart: "You shall be silent and unable to speak until the day when these things take place, because you did not believe my words..." (v. 20).
Mary's question for Gabriel was quite different: "How can this be, since I am a virgin?" (v. 34). It appears that she was not doubting Gabriel's message or integrity (or by extension, the Lord's abilities to accomplish this miracle). Rather, the mechanism of her becoming pregnant did not make sense to her since she had never known a man. Gabriel's response again informs us as to the hidden, spiritual reality occurring in the heart of the one who received the message: "The Holy Spirit will come upon you, and the power of the Most High will overshadow you; and for that reason the holy Child shall be called the Son of God" (v. 35). In other words, Gabriel explained to Mary how she would become pregnant without knowing a man. Gabriel also told Mary the result of the miracle: she would give birth to the Son of God.
In the end, things worked out well for both Zacharias and Mary. Mary, of course, received the privilege and honor of giving birth to and raising the Messiah of the world. Zacharias found his punishment for his unbelief to be relatively brief. Once he regained his ability to speak, he was filled with the Holy Spirit as he, in reference to his son that would become known as John the Baptist, made one of the most beautiful and meaningful proclamations in all of Scripture:
"Blessed be the Lord God of Israel,
For He has visited us and accomplished redemption for His people.
And has raised up a horn of salvation for us.
In the house of David His servant—
As He spoke by the mouth of His holy prophets from of old—
Salvation from our enemies,
And from the hand of all who hate us;
To show mercy toward our fathers,
And to remember His holy covenant,
The oath which He swore to Abraham our father,
To grant us that we, being rescued from the hand of our enemies,
Might serve Him without fear,
In holiness and righteousness before Him all our days.
And you, child, will be called the prophet of the Most High;
For you will go on before the Lord to prepare His ways;
To give to His people the knowledge of salvation
By the forgiveness of their sins,
Because of the tender mercy of our God,
With which the Sunrise from on high will visit us,
To shine upon those who sit in darkness and the shadow of death,
To guide our feet into the way of peace" (Luke 1:68-79).