5 key facts about the First Council of Nicaea

On this day in the year 325, the first Ecumenical Council in the history of the Catholic Church concluded: the Council of Nicaea, which arose as a response to the heresy of Arianism, which stated that Jesus Christ was an inferior God.

Coinciding with the Jubilee of HopeNext year, 2025, the 1,700th anniversary of this great event of the Church in which Jesus was recognized as “true God of true God” will be celebrated.

Within the framework of this upcoming anniversary, we remember 5 keys that every Catholic should know:

1. Why was it called?

The first Ecumenical Council in history took place from May 20 to July 25, 325 in Nicaea and was attended by bishops from all regions where there were Christians.

This event was celebrated to achieve the unity of the Church, shaken by the preaching of Arius, a priest who denied the true divinity of Jesus Christ.

2. Who participated?

There were a total of 300 Council Fathers who participated in this event. Among them, the presence of Alexander of Alexandria stands out, helped by the then deacon Athanasius, who would become bishop, and declared a saint after his death. The latter would be essential in the fight against the Arian heresy.

In the book 50 questions about Jesus Christ and the Churchprepared by a group of professors from the University of Navarra (Spain), other relevant bishops are cited, such as Osio, bishop of Córdoba, who would have presided over the sessions.

Marcellus of Ancyra, Macarius of Jerusalem, Leontius of Caesarea of ​​Cappadocia and Eustathius of Antioch Eusebius of Caesarea, among others, also participated.

Sylvester I, then Bishop of Rome, did not participate in the Council due to his advanced age, so a group of priests attended on his behalf.

3. What was Arianism?

At the beginning of the 4th century, Arius gave rise to a heresy that took the name Arianism. According to him, Jesus Christ was not God: although he pre-existed the birth of Mary’s womb, he was created in time.

By holding this theory, he denied the eternity of the Word, which is equivalent to denying his divinity. He admitted the existence of God who was unique, eternal and incommunicable; The Word, Christ, is not God, he is a pure creature, although more excellent than all others.

Although Arius focused all his teaching on stripping Jesus Christ of divinity, he also included the Holy Spirit, who was also a creature, and even inferior to the Word.

According to Catholic Encyclopedia, Arianism “described the Son as a second, or inferior, God. Only God was beginningless, uncreated; the Son was created, and had once not existed.”

According to Benedict XVI in one of his catechisms in 2007Arianism posed “a threat to faith in Christ, reduced to an ‘intermediate’ creature between God and man.”

This heresy spread and led to a serious crisis, so the council was called to find a solution.

4. The influence of Emperor Constantine

Although Emperor Constantine influenced its celebration and welcomed the council fathers, the documents show that he did not influence the formulation of the faith that was made in the Creed.

The book 50 questions about Jesus Christ and the Church highlights that the emperor did not have theological capacity to master the issues debated.

In fact, although he was not an arianConstantine gradually relaxed his anti-Arian position under the influence of his sister, who had Arian sympathies.

The emperor ordered a final session to be held, which he attended to exhort the bishops to work for the maintenance of peace; He entrusted himself to his prayers and authorized the fathers to return to their dioceses.

5. Conclusions of the Ecumenical Council

The First Council of Nicaea achieved an orthodox definition of faith and the use of the term homoousios (consubstantial, of the same nature) to describe the nature of Christ.

From this event arose what is known as I believe Nicene-Constantinopolitana dogmatic declaration of the contents of the Christian faith that reflected the faith received and accepted by Christians from the beginning.

After the Council of Nicaea they were Arius’s writings were condemned and he and his followers were banished.

Likewise, in Nicaea the celebration of Easter was set on the first Sunday after the first full moon of spring, following the usual practice in the church of Rome and many others.

Some disciplinary issues relating to the internal functioning of the Church were also discussed, summarized in 20 cannons.

Among other things, all members of the clergy were prohibited from residing with any woman except their mother, a sister, or an aunt; It was also established that Bishops, priests and deacons cannot move from one church to another; Rules regarding excommunication were determined and it was established that on Sundays and during the Easter season prayers must be said standing.