Zoo-
When you wrote "give me a break" I sensed a little attitude. But thats ok, I understand your ignorance about this topic on halos. But please, open your mind and your heart, and read the information below. As you will read below the catholic religion acknowledges that the halos were a pagan symbol.
Why is a halo put on the head of a statue of a Saint, and what is its symbolic meaning?
The halo, or circle, which is supposed to represent a ring of light, is symbolic of the light of grace bestowed by God. It may be regarded in art as the development of the aureole, the nimbus and the gloria.
The aureole is a cloud or glow of light in oval form surrounding the whole figure. The nimbus is a cloud or glow of light around the head. The gloria is light emanating from the body.
The halo or nimbus around the head of Christ is symbolic of His divinity.
The pagans used such devices before the Christian Era to signify power and majesty or prominence. Even in the Christian Era the symbols were used for famous personages, but Pope Urban III (1623- 1644) forbade the use of the nimbus for persons who are not at least beatified.
Source: The Catholic Universe Bulletin, Official Newspaper of the Cleveland Diocese, August 14th, 1942, The Question Box.
--------------------------------------------------------------------------------
In the plastic arts (painting and sculpture) the symbolism of the nimbus was early in use among the pagans who determined its form. In the monuments of Hellenic and Roman art, the heads of the gods, heroes, and other distinguished persons are often found with a disc-shaped halo, a circle of light, or a rayed-fillet. They are, therefore, associated especially with gods and creatures of light such as the Phoenix. The disc of light is likewise used in the Pompeian wall paintings to typify gods and demigods only, but later, in profane art it was extended to cherubs or even simple personifications, and is simply a reminder that the figures so depicted are not human. In the miniatures of the oldest Virgil manuscript all the great personages wear a nimbus. The custom of the Egyptian and Syrian kings of having themselves represented with a rayed crown to indicate the status of demigods, spread throughout the East and the West. In Rome the halo was first used only for deceased emperors as a sign of celestial bliss, but afterwards living rulers also were given the rayed crown, and after the third century, although not first by Constantine, the simple rayed nimbus. Under Constantine the rayed crown appears only in exceptional cases on the coin, and was first adopted emblematically by Julian the Apostate. Henceforth the nimbus appears without rays, as the emperors now wished themselves considered worthy of great honour, but no longer as divine beings. In early Christian art, the rayed nimbus as well as the rayless disc were adopted in accordance with tradition. The sun and the Phoenix received, as in pagan art, a wreath or a rayed crown, also the simple halo. The latter was reserved not only for emperors but for men of genius and personifications of all kinds, although both in ecclesiastical and profane art, this emblem was usually omitted in ideal figures. In other cases the influence of ancient art tradition must not be denied.
Source: The Catholic Encyclopedia, 1913 edition, online - Nimbus.