To be deep into history, John Henry Newman wrote, is to cease to be a Protestant. Put another way, to be deep into history is to become stronger in the Catholic faith—something we are all called to do in this Year of Faith.
To make that journey into the history of our faith is to discover anew its most basic tenets. Who was Jesus really? How can God be three persons in one being? What is the proper role of the Church in salvation? And how does Mary fit into all this?
These questions, and many more, were raised and answered in the ecumenical, or universal, Church councils.
Ironically, one key to understanding the orthodox teachings of these councils is heresy. The councils, especially the earliest ones, were essentially anti-heresy conventions, called to sort the wheat of dogma from the chaff of heresy. This could be a dizzying and disorderly process: no sooner had one bastion of orthodoxy had been defended, than the Church had to rush to the defense of another. So, while one council had to correct heretics who falsely divided Christ into two persons, the next council had to make a course correction in the other direction, reining in heretics who falsely united His human and divine natures into one.
“To have fallen into any one of the fads from Gnosticism to Christian Science would indeed have been obvious and tame,” G. K. Chesterton wrote in Orthodoxy. “But to have avoided them all has been one whirling adventure; and in my vision the heavenly chariot flies thundering through the ages, the dull heresies sprawling and prostrate, the wild truth reeling but erect.”
In all, there were 21 ecumenical councils. All were important in their time, but only some of them stand out for the lasting significance they have had on the faith and life of the Church today. Here, then, are the top ten must-know councils, listed chronologically by the date they were convened:
1. First Council of Nicaea, 325: One of the earliest heresies to rear its head was Arianism, which asserted that Christ was created by the Father and later adopted as His Son. Refuting this heresy—by declaring Christ one in being with the Father—was the chief task of the Council of Nicaea. In the process, the Nicene Creed was born.
2. First Council of Constantinople, 381: This council defended dogma on two fronts. It affirmed the divinity of the Holy Spirit as the third person of the Trinity. And it condemned a new heresy that claimed Christ was part man and part God but not completely one or the other. Instead, the heresy, known as Apollinarism, put forward the harebrained theory that Christ was comprised of a human body and a divine mind.
3. Council of Ephesus, 431: This council defined the dogma that Christ is one person, not two persons, as the heretical Nestorians claimed. This council also has the distinction of being the only ecumenical gathering that made any dogmatic statements about Mary, declaring her to be the Theotokos, or Mother of God. The other great achievement of this council is its least known: repudiation of one of the most insidious of heresies in Christian history—Pelagianism, which denied original sin and said men can use their free will to attain salvation on their own merits, without God’s grace.
4. Council of Chalcedon, 451: After Ephesus declared that Christ was one person, some Christians took that teaching too far, concluding that He also had just one nature, a mystical blend of the human and divine (this heresy was known as Monophysitism, from the Greek words for one and nature). That obviously throws a wrench in the entire message of the gospel. If Christ wasn’t fully man, had mankind really been redeemed? If He wasn’t fully divine, had God really saved us? Needless to say, the Church quickly pulled together another council to clarify its earlier teaching: Christ was one person, but had two natures. The council ended up achieving more than it bargained for, in ways good and bad. On the upside, it helped to cement the primacy of the Pope as the leader of the Church. But it had the tragic and unintended consequence of sending the Orthodox churches in Syria, Egypt, and Ethiopia into schism.