The word “angel” comes from the Greek word aggelos (άγγέλoς), itself a translation of the Hebrew mâI'âk (messenger), which appears also in Ugaritic, Arabic, and other Semitic languages. Although the angel is most often linked with the Judeo-Christian tradition and faith, many different religions that predate them also have divine messengers who intermediate between the visible and invisible worlds (the profane realm and the realm of the sacred), between Gods (deities) and man, and the living and the dead. One can hypothesize that the model of the Christian angel-messenger was formed over the ages in various and fluctuating ancient cultures such as the Syrian, Mesopotamian, Hindi, Chinese, Egyptian, Greek, Roman, Mazdaic, as well as pagan mythologies.

The plethora of scientific, para-scientific, or popular items on angels suggest that one can talk of the discipline of angelic science (angelology). The development of this quasi-science can be observed from the starting point of the notion of angelic choirs in the Middle-Ages through to the magical function of angels in contemporary occultism and the popularity of angels in the New Age Movement.

Pre-Christian Angels

From the outset angels were grouped into ranks or hierarchies in accordance with the astrological theory of planetary spheres. Through the centuries and cultures there have been various representations of angels in the fine arts, but within these exist many elements in common with later Christian representations. They often appeared in an anthropomorphic form that emphasized their mission to humanity, with wings symbolizing their spiritual, ethereal, and celestial nature.

In the ancient Hindu religion, there were invisible creatures with the function of divine messengers called agni (sacrificial fire), angiras (demigods), aditiows (twelve spiritual deities that fight evil forces, and reward the good), and maruts (storm deities that rule over life energy and help fight demons). The Veda tells of guardians of the good called gandharvas. Ancient Chinese religions knew two kinds of spirits, the celestial, who were represented anthropologically or animalistically and who maintained the natural order, and the terrestrial, who took care of family life and agriculture. Egyptian sphinxes guarded temples and palaces and were visualized as winged lions with a woman's head; these had a rapidly increasing influence on Assyrian, Jewish, Phoenician, and Greek cultures. This symbol had a negative connotation, for those who tried to get into guarded places were punishable by death in a variety of ways.