We have seen recently the date that marks the 1700 year anniversary of the Council of Nicaea, and the Creed that the fathers of that Council promulgated. Pope Francis referred to this anniversary in his Bull of Indiction for the Jubilee Year (n.17).
The Council of Nicaea sought to preserve the Church’s unity, which was seriously threatened by the denial of the full divinity of Jesus Christ and hence his consubstantiality with the Father. Some three hundred bishops took part, convoked at the behest of the Emperor Constantine; their first meeting took place in the Imperial Palace on 20 May 325. After various debates, by the grace of the Spirit they unanimously approved the Creed that we still recite each Sunday at the celebration of the Eucharist. The Council Fathers chose to begin that Creed by using for the first time the expression “ We believe”, as a sign that all the Churches were in communion and that all Christians professed the same faith.
Pope Francis drew attention to the ecumenical implications of the anniversary, as did Pope Leo XIV in his meeting with representatives of other Churches and Ecclesial Communities, as well as other religions, who had attended the inauguration of his pontificate:
The Council of Nicaea was a milestone in the Church’s history. The celebration of its anniversary invites Christians to join in a hymn of praise and thanksgiving to the Blessed Trinity and in particular to Jesus Christ, the Son of God, “consubstantial with the Father”, who revealed to us that mystery of love. At the same time, Nicaea represents a summons to all Churches and Ecclesial Communities to persevere on the path to visible unity and in the quest of finding ways to respond fully to the prayer of Jesus “that they may all be one. As you, Father, are in me and I am in you, may they also be in us, so that the world may believe that you have sent me” ( Jn 17:21).
And in the words of Pope Leo XIV:
My election has taken place during the year of the 1700th anniversary of the First Ecumenical Council of Nicaea. That Council represents a milestone in the formulation of the Creed shared by all Churches and Ecclesial Communities. While we are on the journey to re-establishing full communion among all Christians, we recognise that this unity can only be unity in faith. As Bishop of Rome, I consider one of my priorities to be that of seeking the re-establishment of full and visible communion among all those who profess the same faith in God the Father, the Son and the Holy Spirit.
A "Creed", such as that of Nicaea, can also be referred to as a "profession of faith". This latter designation draws attention to a two-fold aspect of such a formulation - the content expressed in the text, and the affirmation by the faithful of their adherence to that content. A moving instance of such a profession of faith, in this second sense, is to be found in that made by Pope St Paul VI on 30th June 1968 as he closed the Nineteenth Centenary of the martryrdom of St Peter and St Paul, and which has since come to be known as The "Credo" of the People of God.
Furthermore, We consider it Our duty to fulfil the mandate given by Christ to Peter, whose successor We are in spite of Our unworthiness - the command "to confirm Our brethren" in faith. Therefore, although We are conscious of Our inadequacy, We nonetheless will make a profession of faith with all the strength that our Spirit draws from the mandate We have received. We are going to repeat that declaration that begins with the word "Credo" which, though it is not a strict dogmatic definition, still, rightly interpreted in accordance with the spiritual requirements of our times, recapitulates in substance the formulation of Nicaea - the formulation of the immortal tradition of the Holy Church of God.
Expanding from the profession of faith that is now recited at Mass, Pope St Paul VI offers a beautiful and wide ranging summary of Catholic belief that will reward a re-reading.