Welcome to Defenders, the teaching class of Dr. William Lane Craig.

Today, the Doctrine of the Trinity.

Part 7.

For more information and resources from Dr. Craig, go to reasonable faith.org.

In our study of the Trinity, we've looked so far at the Lagos Christology of the early Greek

apologists and then at modalism.

And now we come to the subject of Arianism.

In the year 319, a presbyter of the Church of Alexandria, Egypt, named Arias, began to propagate his doctrine

that the son is not of the same substance as the father. You remember that according to Tertullian and other church

fathers who opposed those who denied the full deity of Christ, that Christ is of the same substance

or essence as the Father and therefore fully divine.

Arius denied that Christ is the same substance as the Father.

Rather, he said that Christ had been created by the Father

before the beginning of the world.

And this episode marked now the great Trinitarian controversy that would occupy the church until the end of the century and give

us the Nicene Creed and the Constantinopleitan creeds as a result.

Now you'll remember that Tertullian thought that the Lagos was begotten by God the Father

at the beginning of creation. By contrast, Alexandrian theologians like Oregon held that the begetting

of the Son or the Logos from the Father did not have a beginning. Rather, it was an eternal

begetting that had always taken place. And Arias thought that the reason that the Orthodox theologians were so opposed to his view

that the Son had a beginning was because he affirmed that the Son did not exist eternally.

In his letter to Eusebius of Nicomedia, he affirmed, and I quote,

...