Alexander of Alexandria: Epistles to Clergy and Churches - 318 A.D.

Some of the first rumblings of Arian Hersey that would lead up to the Council of Nicea.
Arius was a mere presbyter from the region of Alexandria and his view was spreading more and more to the point where the local Bishop (Patriarch) of the city, Alexander, was forced to intervene.. initially by writing these letters of warning and also to get affirmations of faith from the surrounding churches.