The early Creeds of the Eastern Churches, like that which Eusebius of Cæsarea proposed at Nicæa, expressly declare the unity of God, in opposition both to the heathen Polytheism, and to the various heresies which introduced two or more Gods.  See below in this Lecture, §§ 12–18; and compare Athan. (contra Gentes, § 6, sqq.)