"Then war broke out in Heaven. Michael and his angels waged war upon the dragon. The dragon and his angels fought, but they had not the strength to win, and no foot-hold was left them in Heaven. So the great dragon was thrown down, that serpent of old that led the whole world astray, whose name is Satan, or Devil — thrown down to the earth, and his angels with him." (Revelations XII: 7-9). The fallen or malevolent Archangel Lucifer became the Devil of Judaism, Satan of the early Church, and Iblis of Islam.

The most important function of angels in Judaism, Zoroastrianism, Christianity and Islam is to praise God and do His will. In Zoroastrianism, angels are called the amesha spentas or bounteous immortals, functional aspects of Ahura Mazda, the wise Lord. They are arranged in a hierarchy of seven: Spenta Mainyu (the Holy Spirit), Vohu Manah (Good Mind), Asha (Truth), Armaiti (Right-mindedness), Khasathra Vairya (Kingdom), Haurvatat (Wholeness) and Ameretat (Immortality). Vohu Manah in the 6th century B.C. revealed to Zoroaster the true God, his nature, and an ethical code. In later Zoroastrianism, Ahura Mazda and Spenta Mainyu are identified with each other. Counterpart of the bounteous immortals are Angra Mainyu, the evil spirit that subsequently became the antagonist Ahriman. Arrayed with Angra Mainyu against Ahura Mazda were Akoman (Evil Mind), Indra Vayu (Death), Saurva, Nanhaithya, Tauru and Zairi.

In both Judaism and Christianity, "angel" denotes a spiritual being, one of the unseen citizens of Heaven, who are continually awaiting and doing the bidding of the Most High. They are pure spirit; neither male nor female (though referred to for convenience as "he"), they are messengers and a means of revelation of God to man. In the most ancient edition of the Bible the "Angel of God" is God Himself in self-manifestation. Sometimes the angel has no form and is only a voice, as when the Angel of God spoke to Jacob in a dream. Occasionally, the angel is in the form of a man, as when the birth of his son was foretold to Abraham, Lot was warned to leave Sodom, and "an angel" wrestled with Jacob. In the later editions of the Old Testament, angels were depicted as messengers and executors of the Lord’s commands. For example, an angel went before the children of Israel to guard and guide them into the Promised Land; and an angel was sent to punish King David for having taken a census of his people.

In the Old Testament, angels were also called "sons of God", sons of the Mighty", "holy ones" and "watchers". That they are warriors is implicit in such phrases as "Lord of hosts" and "the heavenly host"; the Old Testament mentions Seraphim and Cherubim as well. Seraphim six-winged angels, belong to the highest of the nine orders of angels and continually sing the praises of God; Cherubim are also winged beings with human faces and are associated with the throne and chariot of God. In the Old Testament book of Genesis, Cherubim are the guardians of the approach to the Tree of Life. In the book of Ezekiel they have a human body with a head presenting the faces of a man, a lion, an ox and an eagle, four hands and four wings; the whole body of the Cherubim and the wheels of the chariot furnished with innumerable eyes.

The Archangels — Michael, guardian of Israel, Gabriel, ruler of Paradise and Raphael, guardian of human spirits — also appear in the Old Testament. Venerated by the Jews, from the beginning of Christian history, there is evidence of the honour in which Michael was held. The well-known passage from Revelations, quoted earlier, contributed to him being honoured in the West as the "captain of the heavenly host" and protector of Christians in general and soldiers in particular. In the East, he was looked on as special guardian of the sick. Outside Constantinople, there was a church named after him from the time of Constantine (274-337).

Veneration of Michael was intensified by visions of him believed to have been seen in Italy, France, England, Germany and elsewhere. A great impression was also made by the story that, during a plague in Rome, Pope Gregory I saw the Archangel sheathing his sword above Hadrian’s mausoleum (now called the Castle of St Angelo). All over Christendom, chapels dedicated to St Michael were built on top of hills and mountains. A contemporary popular song of Black American folk origin, "Michael row the boat ashore! Alleluia!" seems to incorporate a reminiscence of the very old tradition of Michael as the receiver of the souls of the dead.

No other individual archangel had a feast day in the calendar of the Western Church until the present century, although both Gabriel and Raphael have always been venerated by the Eastern Church; Today, Gabriel, who foretold the birth of Jesus to Mary, is commemorated by the Roman Catholic Church on March 24, and Raphael on October 24. From the meaning of his name "God heals", Raphael is assumed to be the angel "who troubled the water of the pool called Bethesda near Jerusalem". The first person who stepped into the pool after the "troubling" was healed of whatever disease afflicted him or her.

More angelic names appear in the non-canonical books of the Bible: Uriel, leader of the heavenly hosts and guardian of Sheol, the underworld, Reguel, avenger of God against the world of lights, Sariel, avenger of the spirits "who sin in the spirit", and Ramiel, also called Jeremial, guardian of the souls in Sheol. It is interesting that the Dead Sea Scrols mention sects which included the angels of light, darkness, destruction and holiness with the higher angels.

Jesus, ministered to by angels after his temptation, mentions guardian angels: and an angel strengthened him in the Garden of Gethsamane before the Crucifixion. An angel spoke to the women at the sepulcher on the first Easter morning, while another spoke to the disciples at the Ascension. Later, angels appeared to Peter, John, Philip, Cornelius and Paul. And we learn from St Paul of Thrones, Dominions, Principalities, Power and Virtues or Mights. The Angels of the Seven Churches in Revelations are, however, either the chief overseers or the personifications of those churches.

The De Hierarchia Celesti, a 5th century treatise, systematises the evidence offered by Judaism and Christianity and concludes that there are three hierarchies of angels, each consisting of three orders: seraphim, Cherubim, thrones; dominions, mights, powers; and principalities, archangels, angels.

Influenced by the concepts of Judaism and Christianity, Islam too developed a hierarchy of angels. First, there are the hamalat al’arsh, the four throne-bearers of Allah, who following the imagery in Revelations in the New Testament, are symbolised in Islamic legend by a man, a bull, and eagle and a lion. Next, there are the karubiyum or cherubim who sing the praises of Allah. Then there are the four archangels: Jibril (Gabriel) the Revealer, Mikal (Michael) the Provider, Izra’il the Angel of Death and Israfil the Angel of the Last Judgement. Lastly there are lesser angels such as the hafazah or guardian angels.

Angels wings are symbolic of their heavenly origin, their invisible and spiritual nature, and the speed with which they hasten to do God’s will. Although the importance of angels lies chiefly in what they do rather than in what they are, popular piety influenced by pictorial and symbolic presentations of angels has imbued them with essential identities and credits them with semi-divine or even divine status.

In the 16th century when Copernicus with his discoveries radically altered the view of the universe so that succeeding generations no longer believed the earth to be the centre of the cosmos, but accepted instead that it was only a small planet in a small solar system which was in turn a very small part of a galaxy in an apparently infinite universe, angels and demons and a tripartite cosmos seemed anachronistic.

However, the Freudian "myth" of the tripartite human personality — the superego or the restrictive regulations that enable man to live as a social being, the ego or the conscious aspects of man, and the id or libido a "seething, boiling, cauldron of desire that seeks to erupt from beneath the threshold of consciousness" — has given a new dimension to the study of angels and demons, and these have taken on fresh and deeper meanings.

However, despite psychology and psychoanalytical studies and the fact that no one today can reasonably believe that the universe is tripartite, angels as motifs in art and as characters in stories have certainly been an enriching element of human experience.