Angels depicted in early Christianity served a primary purpose for early Christians, which was to represent to human beings the intentions of God, and as such were considered messengers or representatives of God. Their primary intent seemed to be not only to communicate messages from God, but to act within history to direct his purposes as well. Depiction of angels in Christianity has evolved over time, changing significantly after the First Ecumenical Council in the late fourth century.

Angels in the Old Testament

Early Christians used the Hebrew Scriptures (which came to be known as the Old Testament) in order to understand angels. In the Old Testament the patriarch, Jacob, wrestles with an angel, who is specifically said to stand in the place of God. Angels appear throughout the Scriptures to bring messages or to direct people, to protect certain people (such as the three Hebrew children cast into an Egyptian furnace) or to act in judgment (such as the angel of death who appears in the book of Exodus). More obscure texts refer to angels as manifesting the will of God by fighting against evil spirits, appearing as an invisible army to Elijah, or appearing as men to Abram and others, as well as in the Apocryphal book of Tobit, when an angel guides Tobit's son to his future bride, who is tormented by evil spirits.

Angels in the New Testament

In the New Testament the purpose of angels is revealed specifically in the events leading up to the birth of Christ. Angels appear to Mary (the mother of Jesus) and to her cousin Elizabeth (mother of John the Baptist) to tell them of their role in giving birth to their respective sons. They also appear to shepherds to announce the birth of Christ on the night he is born. Peter advises in a New Testament epistle to be hospitable to everyone because "many have entertained angels unaware." In Paul's epistle to the Ephesians, he describes angels as hierarchical beings with at least nine ranks. Prophetic books in the Old Testament, as well as Revelation, depict angels as surrounding the throne of God, worshipping God continuously.

The Evolution of Angels

The First Ecumenical Council in the late fourth century put to rest the notion that Jesus was an angel, an idea that was present among some early Christians. A majority of the bishops present affirmed that Jesus was not an angel, but that angels were an ethereal type of being, a creature somewhat like humans but without physicality as we know it. Prior to this time, angels were not depicted with wings. The introduction of wings in Christian art after the fourth century was not meant to be a literal representation, but to symbolize the ethereal nature of angels. Ellen Muehlberger, a scholar at the University of Michigan, writes in regard to winged angels that "in antiquity, some Christians believed that angels were minds, or intellects, detached from bodies."

Angels and Demons

While angels were considered to be God's representatives who reflect his glory, the early Christian church generally regarded demons and evil spirits to be the angels who had rebelled against God. The serpent in the book of Genesis who tempts Eve to partake of a fruit which God has forbidden her was understood by early Christians such as Tertullian, an early church writer, as the fallen angel, Lucifer (or Satan), who led a rebellion in heaven. As disembodied intellects in early Christianity predisposed to evil, demons could therefore possess vulnerable individuals to behave irrationally. In time, various temptations and vices would be attributed to the influence of demonic entities. As a counterpart, the notion of guardian angels developed simultaneously as those appointed by God to protect individuals from the devices of a fallen, demonic enemy.