In n.17 of the document Pope Francis draws our attention to the 1700th anniversary of the Council of Nicaea.
“The coming Jubilee Year will also coincide with a significant date for all Christians, namely, the 1700th anniversary of the celebration of the first great Ecumenical Council, that of Nicaea. It is worth noting that, from apostolic times, bishops have gathered on various occasions in order to discuss doctrinal questions and disciplinary matters. In the first centuries of Christianity, synods frequently took place in both East and West, showing the importance of ensuring the unity of God’s People and the faithful proclamation of the Gospel. The Jubilee can serve as an important occasion for giving concrete expression to this form of synodality, which the Christian community today considers increasingly necessary for responding to the urgent need for evangelization. All the baptized, with their respective charisms and ministries, are co-responsible for ensuring that manifold signs of hope bear witness to God’s presence in the world.”
It was at this Council that the bishops present discussed, debated and finally decided, the wording of the Nicene Creed, the Creed we usually proclaim together on Sundays. The main theological point that had to be discussed and defined is mentioned by Pope Francis in n.17 as well. At the time there was a threat to the unity of the Church because some people were denying the full divinity of Jesus Christ. That is why we have the section in the Creed that reads ‘God from God, Light from Light, true God from true God, begotten, not made, consubstantial with the Father’. It is there to highlight that truth of our faith of Christ being divine.