At an ecumenical prayer service in St Peter’s Square before the Synod of Bishops in 2023, the late Pope Francis reminded Christian leaders of the power of prayer to help unite us and break down denominational differences.
“The more we turn together to the Lord in prayer, the more we feel that it is he who purifies us and unites us beyond our differences”, the pope said.
“Christian unity grows in silence before the cross, just like the seeds we will receive, which represent the different gifts bestowed by the Holy Spirit on various traditions: it is up to us to sow them, in the certainty that God alone brings about growth”, Pope Francis added.
In May 2025, Christian communities around the world are marking the 1700th anniversary of a landmark event which presents an invaluable opportunity to take up the call of the late Pope Francis and come together in prayer with other Christians united in our common baptism.
The Council of Nicaea in 325 was the first ecumenical council as it brought together bishops from across the Christian communities at that time. The creed which emerged from the heated debates of the council has remained in the Christian consciousness ever since.
Of greatest significance from the Council of Nicaea was its definition of the divinity of the Son as “consubstantial” to the Father, or “begotten of the Father”, as we recite in the Nicene Creed, in other words, of the very substance of the Father.
As emphasised in the International Theological Commission’s report, Jesus Christ, Son of God, Saviour’ released to mark the 1700th anniversary of the Council of Nicaea, this central clause of the creed means “the Son is not only fully God as the Father, but even of a substance numerically identical to his own, since there is no division in the One God”.
The great father of Orthodoxy, St Athanasius, who was a young deacon at the Council of Nicaea, fought strongly to defend Jesus Christ as true God and true man and defend the Holy Trinity. His strongest opponent at the council, Arius, believed the Son could only ever be inferior to the Father.
Nearly 2000 years later, the Nicene Creed continues to remind us what unites us as Christians: a common belief in a Trinitarian God, in Jesus Christ, true man and true God, salvation in Jesus Christ according to the Scriptures. The creed also affirms our shared beliefs in baptism, the resurrection of the dead and eternal life.
It is not surprising then that the 1700th anniversary of the Council of Nicaea is the central theme for this year’s Week of Prayer for Christian Unity, held in the southern hemisphere from 1-8 June.
Coordinated annually by the World Council of Churches and the Vatican’s Dicastery for Promoting Christian Unity, Christian churches are invited to unite at the local level in services between the feasts of the Ascension and Pentecost, the birthday of the church.
Christian churches are invited to recite the Nicene Creed together, pray together and listen to a selection of readings across the week, taken from not only our own Lectionary, but also reflections from great Christian writers in the Greek, Armenian and Syriac traditions. Resources to assist parishes including specific prayers and readings can be found on the National Council of Churches of Australia website.
While the celebration of the Eucharist as one Christian church continues to be an obstacle, all Christians can unite around prayer and the Liturgy of the Word, united by our common baptism.
In many respects, this is one of the great legacies of Vatican II and this year’s anniversary of the Council of Nicaea is an opportunity to renew our appreciation of what the council achieved, the progress made over recent decades on ecumenism and to look ahead on the path to Christian unity.
Prior to Vatican II, many Australian Catholics will remember a far more sectarian society in which Catholics and Protestants would be discouraged from entering each other’s churches, including for special occasions such as weddings.
Released in 1964, while the Second Vatican Council discussions were underway, the landmark decree on ecumenism, Unitatis Redintegratio signalled from its opening paragraph that the restoration of unity among all Christians was one of the principal concerns of Vatican II.
There was a timely recognition of the common baptism amongst Christians and a call to embrace fellow baptised Christians as brothers and sisters with respect and affection. It celebrates the sacramental bond of baptism, a bond of unity which links all who have been reborn by it.
Pope St John Paul II very much built upon the foundations set in Vatican II in his 1995 encyclical, Ut Unum Sint, meaning “That They May Be One”, taken from John 17:21. The Polish-born pope acknowledged what he described as “the gifts of grace” across other Christian communities.
In a major step-forward for ecumenism he wrote: “Many elements of great value, which in the Catholic Church are part of the fullness of the means of salvation and of the gifts of grace which make up the Church, are also found in the other Christian communities”.
Thirty years later, we can see the fruits of Ut Unum Sint through ecumenical prayer services in Australia and in many other countries and the anniversary of the Council of Nicaea presents an opportunity to make such services more common practice.
The Catholic Church has indeed made efforts to bridge differences with Orthodox churches to ensure the East and West can unite in ecumenical prayer services centred on the Nicene Creed. The text of the creed used in such services is normally the Nicene-Constantinopolitan Creed. In referring to the Holy Spirit, it leaves out the so-called “filioque clause”—“and the Son” after the phrase “who proceeds from the Father”. This clause was not included in the text of the creed adopted at the Council of Nicaea or at the Council of Constantinople less than 60 years later, but was added in the West in the 6th century, so as to underline the divinity of the Son in the face of the Arian heresy.
One of the goals of the Council of Nicaea which we have yet to achieve is a common date for Easter across the Christian churches. This primarily is because the Eastern and Western branches of Christianity observe the Julian and Gregorian calendars respectively. This year, in the year of the Nicene Creed anniversary, by happy coincidence all Christians celebrated Easter on the same day. While Pope Francis and the Ecumenical Patriarch Bartholomew had expressed a desire to establish a common date for the celebration of Easter, it may indeed now be up to their successors over coming decades to continue walking together towards that long-held goal of a common date for Easter, the most sacred of Christian celebrations.
Ultimately, what unites all Christians is the Word of God conveyed through the scriptures and the Holy Spirit poured out upon the church at Pentecost. The call to unite as one church is one which Christians can all take from St Paul’s writings, especially Ephesians 4:3-5:
“Do all you can to preserve the unity of the Spirit by the peace that binds you together. There is one Body, one Spirit, just as you were called into one and the same hope when you were called. There is one Lord, one faith, one baptism and one God, who is Father of all, over all, through all and within all.”