“Progress has not followed a straight ascending line, but a spiral with rhythms of progress and retrogression, of evolution and dissolution,” was an astute observation once made by Johann Wolfgang von Goethe (1749–1832). Goethe refutes the idea that the march of time always brings progress and advancement. This applies even to the church. There are times when the church has advanced its understanding of biblical doctrine, and there are other times when its understanding has devolved. We see this throughout history when it comes to the doctrine of God and especially the doctrine of the Trinity.
The early church fought off false teachers and doctrines to obtain a better understanding of what the Bible teaches about who God is and how the Father, Son, and Holy Spirit relate to one another in terms of their existence and works. They thought deeply and biblically regarding the Scripture’s affirmation that we worship one God in three persons: Father, Son and Holy Spirit. In so doing, the church defended biblical truth against three errors: modalism, Arianism, and semi-Arianism. Yet, these errors did not go away but have periodically reappeared throughout church history.