Hundreds of thousands of Christians across Britain and Ireland are joining in the 2013 Week of Prayer for Christian Unity in churches across these islands.
The Week is an annual event marked by churches of all traditions - Catholic, Anglican, Orthodox, evangelical and indigenous. It runs from 18-25 January, though many congregations are most involved on this Sunday, 20 January.
The collaborative event aims at building bridges in witness and common service between Christians of many backgrounds and understandings, and is promoted by ecumenical bodies nationally and internationally.
Here the official 'four nations' (England, Scotland, Wales and both juridictions of Ireland) ecumenical body, Churches Together in Britain and Ireland (CTBI) makes resources available for the week.
The theme for the Week of Prayer for Christian Unity 2013 comes from an ecumenical group in South India. They have reflected upon their own context and offer to people across the globe thematic ideas that call fellow Christians to respond to the obligation to act justly in the world.
The text is taken from Micah 6.6-8 in the section of the Bible that Christians call the Old Testament and many Jews refer to as the Hebrew Bible.
The title for the Week this year is in the form of a challenging question: 'What does God require of us?'
The materials have been adapted by the Britain and Ireland writers group and they have written additional material, including meditations for each of the 8 days, and two versions of the worship service.
Some areas of the world observe the Week of Prayer for Christian Unity at Pentecost or some other time.
To allow for local decision making, the material has only the year on it and the days are denoted by the numbers one to eight, so it may be used at any time of year.
This year, CTBI is continuing its our partnership with the British and Irish based international churches' development agency Christian Aid, who have participated in the preparation of WPCU materials.
Those using them will find within the resources some important pointers to the vital work of Christian Aid in the relief of poverty and advocacy of justice in changing the world.
* The full CTBI resources page for WPCU can be accessed here: http://www.ctbi.org.uk/606/
* People are encouraged to show support for Christian unity on Twitter by using the #wpcu2013 hashtag
* More about the Week of Prayer for Christian Unity on Ekklesia: http://www.ekklesia.co.uk/wpcu
* WPCU: seeking unity through diversity and justice: http://www.ekklesia.co.uk/node/17828
* Why do we pray together? A reflection on Christian unity, by Harry Hagopian: http://www.ekklesia.co.uk/node/17829