Archbishop of Canterbury Justin Welby told journalists that ecumenical unity begins with the nature of one God omnipotent.
Welby, the Church of England leader, shared a platform with Bishop Brian Farrell, secretary of the Pontifical Council for Promoting Christian Unity; Metropolitan Job of Pisidia, the permanent representative of the Ecumenical Patriarchate to the WCC; and Rev. Prof Dr Sandra Beardsall, member of the WCC Faith and Order Commission.
"One God equals one church—more than one church or communion of churches becomes competitive church, and in competitive church, a bad church drives out good churches.
"Unity does not mean a united bureaucracy or even a united hierarchy, or style of worship or common cultural assumptions. It means a profound love for one another that receives each other at the Lord's table.”
Belonging together in Christ
He said it means acceptance of ministry and means the assumption that we belong together to Christ and we treat each other as the Christian family. "It is not identity, but community unity in diversity,” he said.
Beardsall, a professor of ecumenics at St Andrew's College, Saskatoon, in Canada, observed that in 2025, Christians will mark the 1,700th anniversary of the first Ecumenical Council held at Nicaea.
"The Commission on Faith and Order sees this as an opportunity to remember to reflect and to renew the commission's own mandate to serve the churches as they call one another to visible unity," she said.
"The Council of Nicaea in 325 is foundational for Christians. It helped to define the edges and boundaries of Christian faith. It modelled decision-making; it confronted dissent. It learned by doing as it took the first steps to be a church in dialogue with itself and with the world."
Beardsall said that counsel also gives the church much to ponder on the role of state and empire in the church's life and relationships with other faiths.
Farrell said that at the beginning of the church unity conversation, "in the case of most Catholic theologians and the church in general, we understood unity as uniformity - and everybody being alike.
"It has taken a long time to understand that is not the case. That's why I sometimes prefer to use the word ‘communion’ rather than ‘unity' so that people don't think that we're all going to be the same doing the same things thinking the same way."
That is impossible, said Farrell, who works closely with the WCC on other religions on faith matters.
"It didn't happen even in the churches that St Paul himself started. Unity is for the sake of mission so that the world may believe it is not something, therefore, that we do for political, strategic tactical reasons.
"We do it because this is the fundamental mission that Jesus gave to us."
Glass half full, not half empty
Metropolitan Job said that in the last decade, churches sometimes forgot about their mandate and got discouraged because of difficulties.
"We start forgetting our major goal and start being activists in other areas. Of course, Christian unity includes many things, but it's very important to have our main goal, which is unity.
He said it is important to discover how much in common churches have.
"Sometimes we see our differences as stones that not do not enable us to reach unity. But it's important to look positively and to see sometimes the glass not half empty, but half full."