In a sermon to mark the start of the Week of Prayer for Christian Unity on Tuesday, the Rev Bob Fyffe said the movement for unity had “transformed things for the better” since the days of his childhood in Dundee when boys would call him a “wee Proddy” (“wee Protestant”).

The Week of Prayer for Christian Unity is held each year by the church worldwide from January 18 to 25. This year’s theme is ‘All things in common’.

Recalling the Pope’s visit to Britain last September, Rev Fyffe noted how the event of Pope Benedict XVI, the Archbishop of Canterbury and ecumenical representatives leaving Westminster Abbey as friends would have been “unthinkable” just two decades.

“Those who seek the unity of God’s church have come far and achieved much,” he said.

“It is not merely that churches have become more friendly with other churches on a superficial level.

“It is this movement that has helped to overcome some deep rooted enmities that have scared communities, transforming churches to be more open to each other.

“And this has not only changed them, but changed the society around them, making the lives of individuals and families more peaceful, settled, at ease with their community.”

Rev Fyffe went on to say that ecumenism was “not about ecclesiastical cosiness” and that seeking greater unity was a necessary outworking of the calling upon Christians.

The task before believers, he said, was to be recognised as Christians by how well they had loved others.

“To be divided as Christians is to offer poor witness to the world,” he said.

“The call to Christian unity must be more than a dream. [It is] the living out of these high ideals that helps others see that faith can be a source of hope.

“In these days when churches are so consumed by issues to do with churches, it is a powerful witness for Christians to be in the world.”

With hundreds of local initiatives planned by churches for the week of prayer, Rev Fyffe called upon churches to help foster dialogue, offer hospitality, listen and “heal memories” in their neighbourhoods and communities.

Rather than using doctrine to define the “other” or the “outsider”, he said churches needed to create safe spaces where people could cross boundaries.

“Only as a united people, as the whole body of Christ can Christians stand shoulder to shoulder, and overcome the great concerns of these days in partnership with everyone of goodwill,” he said.

“The starting point for our Christian witness is for the Church to become that expression of unity, that model of acceptance and welcome and hospitality that is rooted in God.”

The resources for this year’s Week of Prayer for Christian Unity have been put together by an ecumenical group in Jerusalem and Christians are being invited to pray with them for the unity of the church and justice and peace in the Holy Land.

The resources are available online at www.ctbi.org.uk/512/