In this, Christianity differed from Mohammedanism, which absolutely annihilated its antagonist, and spread its own doctrines without adulteration.
Constantine continually showed by his acts that he felt he must be the impartial sovereign of all his people, not merely the representative of a successful faction.

Hence, if he built Christian churches, he also restored pagan temples; if he listened to the clergy, he also consulted the haruspices; if he summoned the Council of Nicea, he also honored the statue of Fortune; if he accepted the rite of baptism, he also struck a medal bearing his title of "God." His statue, on the top of the great porphyry pillar at Constantinople, consisted of an ancient image of Apollo, whose features were replaced by those of the emperor, and its head surrounded by the nails feigned to have been used at the crucifixion of Christ, arranged so as to form a crown of glory.
Feeling that there must be concessions to the defeated pagan party, in accordance with its ideas, he looked with favor on the idolatrous movements of his court.

In fact, the leaders of these movements were persons of his own family.
CHRISTIANITY UNDER CONSTANTINE.2.To the emperor--a mere worldling--a man without any religious convictions, doubtless it appeared best for himself, best for the empire, and best for the contending parties, Christian and pagan, to promote their union or amalgamation as much as possible.

Even sincere Christians do not seem to have been averse to this; perhaps they believed that the new doctrines would diffuse most thoroughly by incorporating in themselves ideas borrowed from the old, that Truth would assert her self in the end, and the impurity be cast off.

In accomplishing this amalgamation, Helena, the empress-mother, aided by the court ladies, led the way.