This doctrine had it roots in Tertullian, who made the Son subordinate to the Father. Origen took this further by teaching that the Son was subordinate to the Father ''in respect to essence.'' The result was ultimately Arianism which denied the deity of Christ. Arius taught that only God was the uncreated One; because Christ was begotten of the Father it meant Christ was created by the Father. Arius believed there was a time when Christ did not exist. Arius and his teaching was condemned at the Council of Nicea in A.D. 325.36
What God is like, Bible.org, citing Paul Enns, The Moody Handbook of Theology, Moody Press, Chicago, IL, 1989, p. 199
a Christian heresy first proposed early in the 4th century by the Alexandrian presbyter Arius. It affirmed that Christ is not truly divine but a created being. Arius' basic premise was the uniqueness of God, who is alone self-existent and immutable; the Son, who is not self-existent, cannot be God. Because the Godhead is unique, it cannot be shared or communicated, so the Son cannot be God. Because the Godhead is immutable, the Son, who is mutable, being represented in the Gospels as subject to growth and change, cannot be God. The Son must, therefore, be deemed a creature who has been called into existence out of nothing and has had a beginning. Moreover, the Son can have no direct knowledge of the Father since the Son is finite and of a different order of existence.
Arianism, Encyclopedia Brittanica
Arianism Entry in Encyclopedia Brittanica