nine celestial orders of Angels

 

Until the New Testament there were only two orders of angels, the Seraphim and Cherubim. St.Paul added seven new orders.  They are  arranged according to their importance: Seraphim, Cherubim, Thrones, Dominations, Virtues, Powers, Principalities, Archangels and Angels.

 

Link to All About Archangels

Seraphim - a celestial being having three pairs of wings. The first of the nine orders of angels in medieval angelology. They regulate the heavens.
seraphims
Cherubim -sent to guard the gates of Eden. Originally they were depicted as the bearers of God's throne, as charioteers, and as powerful beings with four wings and four faces. Usually shown with blue wings. Here shown with a more acceptable one face.
angel
Thrones called the 'many eyed ones' have the duty of carrying out God's decisions. They are often represented as fiery wheels.
thrones
DOMINIONS - their job is to regulate the duties of the other Angels and ensure that God's wishes are carried out.
dominions

VIRTUES - the Angels of Grace who bring God's blessings to Earth, usually in the form of miracles. Known as the 'brilliant' or "shinning'" ones, they are associated with acts of heroism and bring courage when needed.

angelic shoir
POWERS - their job is to prevent the 'fallen angels' from taking over the world and keeping the Universe in balance, perhaps with celestial music.
memling
   
PRINCIPALITIES - the Guardian Angels of cities, nations and rulers, and guards against the invasion of evil angels.
principalities
Archangels - They carry God's most important messages to humans.  
archangles


 
From Wikipedia:

Angelic Council
Orthodox icon of the seven archangels. From left to right: Jegudiel, Gabriel, Selaphiel, Michael, Uriel, Raphael, Barachiel. Beneath the mandorla of Christ-Emmanuel are representations of Cherubim (blue) and Seraphim (red)
Angel - A typically benevolent celestial being that acts as an intermediary between heaven and earth, especially in Christianity, Judaism, Islam, and Zoroastrianism. A guardian spirit or guiding influence. Clarence
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