What does Luke 1:12 mean?

Western artwork often represents angels as serene people in white robes, or chubby-cheeked infants, typically with feathery wings and harps or trumpets. In truth, these are beings of incredible power and influence. Biblical encounters with angels almost always induce terror; angels are constantly telling those they meet not to be afraid (Luke 1:13; 30; 2:10; Matthew 28:4; Acts 10:3–4; Numbers 22:3; Judges 6:22–23). Not all angelic encounters are positive. In some cases, angels are sent to deliver terrible judgment from God (2 Kings 19:35; 2 Samuel 24:16).

It makes sense, then, that even a God-fearing priest like Zechariah (Luke 1:5–7) would be terror stricken when first seeing an angel. That Zechariah is in the Holy Place of the temple, offering a sacrifice of incense (Luke 1:8–11), means he is alone in this room. As it turns out, the angel is here to bring happy news. Though Zechariah and his wife, Elizabeth, are old, they will finally have the blessing of a child (Luke 1:13). This child will become known as John the Baptist, an important herald of Jesus Christ (Luke 1:17).