A rare coin—the 'Spes public'— struck in Constantinople in AD327, shows a particularly clear depiction of the military standard that became the established one for the Roman army, following the vision accorded to Constantine and his troops fifteen years before. It shows the labarum above a banner with three circles on it.
When the sun happens to be at an elevation of 22° from the horizon, the smile of the circumzenithal arc can appear to touch the 46° halo. Were the cloud cover broken, so that just a part of the halo appeared below the arc, the effect is not a million miles away from the cross in Constantine's labarum. And the vertical line of the 'P', incorporated into the symbol? It is a sun pillar appearing below the sun, of course. Three coins on the vellum below the symbol? Well, it goes without saying that they represent the sun with sundogs, or mock suns, on either side of it.
And let us remember that Constantine, moving on this vision, soundly defeated a force much larger than his own. His opponent made a critical tactical blunder on the advice of pagan priests in coming out of the fortifications of Rome, crossing the Tiber with it at his back and with no room to maneuver or to withdraw. Nor must ever forget the civil results: an end to persecution of Christians... the restoration of Christian property, and freedom of Christian worship wherever Constantine ruled, the council that consolidated the catholic-ortodox faith and discredited the heretics.
"Let us therefore follow after the things which make for peace, and things wherewith one may edify another" [St. Paul's Epistle to the Romans 14:19]
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