The Catholic Catechism calls the existence of angels "a truth of faith to which both Scripture and tradition give clear witness" (no. 328). So we do believe in angels.
The word "angel" tells us what they do, not what they are. They have two tasks: to praise God and to help humans. The word "angel" comes from the Greek angelos translation of the Hebrew mal'ak or messenger. The Bible shows angels, Michael, Raphael and Gabriel, delivering God's messages to women and men.
But angels are not only messengers, they are also guardian angels who watch over humans: "In heaven their angels continually see the face of my Father" (Matthew 18.10). Angels watch over each of the seven churches in Revelation, chapter 2, although here the word "angels" may refer to the bishops of these particular churches.
Take a moment to look through the Bible. Count the number of times it mentions angels. If you leave out the angel stories, what do you have?
The elderly Sarah would not learn that she is to become a mother nor would Samuel's mother learn of his unusual birth. Lot's family would not be warned about Sodom's fate and so they would be destroyed. Elijah would die of despair under the broom tree. The three young men in Daniel would be consumed by the fire in the furnace.
Without angels, neither Elizabeth (Luke 1.11-20) nor Mary (Luke 1.26-38) would find out about their miraculous pregnancies. Zechariah and Joseph wouldn't believe. Without an angel, Joseph may have divorced Mary.
No Glorias would fill the air and no shepherds would visit the newborn Jesus. Jesus would suffer in the garden (Luke 22.43) with no angels for comfort. No angels would roll away the stone from Jesus' tomb (Matthew 28.2-3) and none would announce his resurrection (Matthew 28.1-7). No angel would free Peter from jail.
What are angels? Christian tradition considers angels to be immortal, bodiless, spiritual beings created before the universe. Since they have intuitive knowledge superior to humans and free will, they could reject God as humans do.
Unlike humans who have that choice continuously during their lives, angels made the choice once and for all. Those that rejected God are called demons and their aim is to lead humans to follow them.
Angels are not infallible as they are holy by their original choice, not by nature. They operate according to their ranks in the celestial realm. Sixth-century Pseudo-Dionysius, and later Thomas Aquinas, spoke of nine choirs of angels, cross-referenced with examples from Scripture.
Only the lowest, archangels and angels, are shown in Scripture to have a direct mission to humans.
Worship of angels which seems to have arisen during Paul's time is repudiated (Colossians 2.18). Christ is greater than the angels and they are his angels: "In Christ everything in heaven and earth was created, things visible and invisible. All were created through him; all were created for him. He is before all else that is" (Colossians 1.16-17).
Angels accompany Christ from his birth to his ascension and surround his throne in heaven. They will appear with him at the end of time when they will gather all humanity before the judgment seat of Christ.
The Church, in the liturgy, joins with the angels to adore God and invokes their assistance. From birth to death, angels surround humanity with their care and intercession so it is fitting that in the funeral rites, the Church prays, "May the angels lead you to paradise."
Perhaps, it's the trivialization of angels in films and images that seems to make angels less valid today. However, when these popular angels do what biblical angels do, they bring to the fore an aspect of biblical and Christian belief.
In ancient times, God spoke to humanity through the prophets and angels. Today numerous witnesses testify to the appearance of angels who rescue them from danger. Angels could be considered God's voice that speaks to us and God's providence that cares for all of creation.
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