For the past year or so, I have been undertaking a study of the Latin language on my own. I studied Latin for a year in high school and for two semesters in college, and about a year ago conceived the idea of "re-learning" the Latin I had studied in the past and extending my knowledge of the language beyond my prior studies. For that purpose I bought a Latin textbook (Latin Made Simple by Doug Julius) and began to study it as frequently as I could. At the same time I also began a study of koine (or New Testament) Greek--which I have found slower going than the Latin!
My study of Latin revived my past interest in Roman history and occasionally when in a bookstore I would browse at books on the topic. Then, a few months ago, I bought a copy of The Illustrated Encyclopedia of the Roman Empire, by Nigel Rodgers. On the whole, I have found the book to be quite illuminating, but I have found myself occasionally irritated by what appears to be an anti-Christian bias on the part of the author. For example, he dismisses Jesus Himself as "obscure but probably heterodox Jewish preacher" (p. 430)--a characterization that I suspect many Biblical scholars would find highly objectionable.
However, what is perhaps one of the strangest statements of this kind by the author regards the 4th century Roman emperor Constantius II. Rodgers describes Constantius as a "fanatical Christian [who] enforced Arianism (a belief that was later declared heretical) upon the empire..." (p. 238). There are a least two problems with this statement. First of all, if Constantius was enforcing Arianism, then he couldn't have been a genuine Christian, "fanatical" or otherwise. To understand this, it is necessary to know what Arianism was (or is, since it is still embraced by religious groups like the Jehovah's Witnesses). Arianism, advocated by a priest named Arius (256-336 AD), denied that Jesus was the eternally existing Son of God, equal to God the Father. Rather, according to Arius, He was the first and most powerful of all beings created by God. In other words, Arianism denies the doctrine of the Trinity (that there is one God, who exists in three eternally existing persons--Father, Son, and Spirit). Given that the doctrine of the Trinity is a cornerstone doctrine of orthodox Christianity, anyone who denies the Trinity cannot be a true Christian, and that would include Constantius.
Second, Rodgers' description of Arianism as "a belief that was later declared heretical" (emphasis mine) is incorrect. In fact, Arianism had been declared heretical before the time Constantius reigned as emperor (337-361), at the famous First Council of Nicea, a meeting of church leaders that took place in 325, several years before Constantius' reign. In fact, ironically, the council of Nicea had been called by Constantius' own father, the emperor Constantine I (known as "the Great"), who ruled between 306 and 337 (Constantine is probably best known as the Roman emperor who finally legalized Christianity within the empire).
In short, as much as an authority on Roman history as Rodgers may be, it would appear that his knowledge of early church history is rather shaky, and/or that a possible bias toward Christianity in his case has compromised a concern for historical (and factual) accuracy. Strangely enough, in browsing through some other books on Roman history, I have sometimes noticed a similar bias on the part of some other authors. Why this should be the case is not clear to me. Still, it does demonstrate the danger for a historian of allowing his/her prejudices to compromise his/her presentation of history.
Image of coin bearing portrait of Constantius II from Wikipedia