Here is an excerpt:
COUNCIL OF NICAEA PREPARES A CREED
SHORTLY AFTER CONSTANTINE unified the Roman Empire under his political and military control, he found another problem was threatening to tear the Empire apart: the conflict between the Arian heresy and orthodox Christians. Far from being fought out only among thinkers and elites, the debate was raging even at the level of popular songs being taught in the marketplace.
The conflict arose when Arius taught that there had been a time when Christ did not exist and that he was lower than God the Father. The orthodox camp, on the other hand, considered Christ a member of the Godhead and equal with God the Father.
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