https://churchhistory101.com/century4-p5.php
The Church Divided | Donatus and Arius, fourth century heretics and heresies - Early Church History 101 - fourth century, Diocletian persecution, Eusebius of...
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https://www.blueletterbible.org/faq/don_stewart/don_stewart_339.cfm
An ancient heresy regarding the Trinity known as Arianism caused much discussion about the nature of God in the fourth century. Arius, a bishop from
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