One of the strange assumptions religious believers make is that the human forerunners who formed and curated our traditions operated under some kind of spiritual protection that kept them from veering off course or making errors. “God wouldn’t let us be wrong about something so important!” Sure, there’s a basic level of faith we must have that we are following something good and true, and that all of it points back to an authentic revelation of God in Jesus. But the sheer multiplicity of Christian streams and convictions is enough to challenge the notion of divinely guaranteed consistency or theological purity. This shouldn’t plunge us into suspicion or despair, but it should pique our interest in the history and evolution of our own religion. It should also dispel the notion that our ancestors couldn’t make mistakes, or that those mistakes cannot affect us today. (It should also keep us humble in regard to our own ability to err and learn.) Very briefly, here are two examples of dramatic transformations from the early centuries of Christianity that are still causing trouble today.

1. Greek Philosophy Hijacks Bible Interpretation

If you told American Evangelicals today that Christianity had been co-opted by new agers or astrologers or dualists who were rewriting our traditions to conform to their own beliefs and selling them back as orthodoxy, there would be panic in the streets (and probably some kind of boycott or hashtag). Yet this is the very sort of thing that happened to Christianity in its early centuries. The thinkers, authors, and apologists we call “church fathers” were a collection of non-Jewish Christian men who defined the doctrines and canons which still define Christianity many centuries later. Some of the most influential church fathers (most notably Origen) were deeply influenced by Greek philosophy, a connection which had inevitable ramifications in the way they synthesized and described their theology. To be sure, many church fathers (like Tertullian) took a strong rhetorical stance against Greek philosophy as inferior to Christianity. But even these thinkers were indelibly locked into the categories and assumptions of Greek scholarship. When they defended the Bible against Greek ideas, they often did so on Greek terms. And when they interpreted the Bible, they did so within that same framework.

I’m not saying the church fathers as a group constitute a “mistake,” or that they did nothing good to benefit or enrich the faith. But their frequent disregard for the fundamental Jewishness of the scriptures and the categorical assumptions they injected into Bible reading and theology set Christianity on a very rocky path. If you believe in humanity’s “fall from perfection” or the “immortality of the soul” or a “spiritual afterlife,” your faith may have been influenced more by these writers (and thus by Plato and Aristotle) than by the actual texts of the Bible. In a few extreme cases, the efforts of the church fathers actually fueled and codified anti-semitic sentiment in the church. That is a path that takes us as far from the heart of scripture and of Jesus as we can get. Modern Christians should learn about the church fathers and read their work critically.

2. Constantine Imperializes and Militarizes Christianity

The legend is well known: In 312 CE at the Battle of Milvian Bridge, military leader Flavius Constantine I looked up and saw a cross in the sky emblazoned with the command, “By this sign, conquer!” He went on to become Caesar Constantine the Great, and to lead armies into war under the banner of the cross of Christ. It is often said that he made Christianity the “official religion” of the Roman Empire, but it is more appropriate to say that he favored it. Roman pagan practices continued, but those wanting to please and impress the emperor would undergo an expedient conversion to Christianity. Constantine reformed Roman imperialism based on “Christian” principles, if that makes any kind of sense. For example, he outlawed crucifixion to honor the death of Jesus and made hanging the new official mode of execution. The empire could still dominate and victimize and terrorize, but it would do so in a way that “honored” Jesus. Christianity had a king on earth, and that king had bloody hands.

Of course, many thoughtful Christians today would cringe at the idea of a “Christian” army or a weapon emblazoned with a cross. At the same time, how many American Christians claim that they live in a Christian empire? How many connect God’s will and blessing with the power and success of that empire? And it is not uncommon in conservative Christian circles to justify the Roman expansion of Christianity as God’s undercover plan to disseminate the religion around the globe. But how can a machine built on death and domination deliver a gospel about peace and reconciliation? The spirit and legacy of Jesus cannot be managed or defended by an empire. Constantinian Christianity represents an abject failure to realize the gospel of God’s kingdom. It should be a byword for us, and we should strive to define ourselves against it in belief and practice.