Why zachariah was blind?

Zachariah, a biblical figure mentioned in the Gospel of Luke, was not literally blind; rather, he was rendered mute by the angel Gabriel as a consequence of his doubt in God's message regarding the birth of his son, John the Baptist. When he questioned the angel about how he could believe such news, he was struck mute until John's birth. This temporary silence symbolized his lack of faith and served to emphasize the miraculous nature of John's conception.