This is the maintenance of the older pre-1870 approach to public worship among Presbyterians in which the 150 psalms of the Word of God in metrical form were exclusively used, and without instrumental accompaniment. The Scottish Psalter of 1650 was traditionally used in the PCEA, but is now supplanted in most congregations by more modern versions either the version produced by Melbourne PCEA in 1991, or the version produced by the Free Church of Scotland in 2003. The principle behind the practice of exclusive psalmody is that Scripture should regulate our worship and that we cannot do better than to use the Word of God in the public worship. The actions of the Free Church of Scotland in November 2010 in relaxing its stance on a capella psalmody have no bearing on the practice of the PCEA. Organisation The PCEA’s supreme assembly is a Synod which meets annually hosted by one of the congregations. The PCEA has a long-standing arrangement enabling ready interchange of ministers with the Free Church of Scotland, and is a member of the International Conference of Reformed Churches (ICRC). More recently, interchange of ministers with the Reformed Churches of New Zealand (2006) and with the Orthodox Presbyterian Church in the US (2007), both also ICRC members, has been approved. The PCEA does not operate its own theological college, but has trained ministers in the Free Church of Scotland College, Edinburgh, at the Reformed Theological College, Geelong, and, more recently, in the training institutions of the mainline Presbyterian Church, supplemented in certain subjects. In Victoria it has friendly relations with the Reformed Presbyterian Church of Australia which has congregations at Geelong, Frankston and MacKinnon, and whose presence in Australia also dates from colonial times. The current communicant membership (31/12/2017) is about 450 with a total community of about 800. At the same date there were 11 ministers in pastoral charges and another seconded to provide leadership for Australian Indigenous Ministries (formerly Aboriginal Inland Mission). A significant work has developed among Sudanese refugees in Melbourne, with one minister from the Nuer people of South Sudan. The main centres are: Northern Presbytery: Brisbane (Woolowin); Northern Rivers (Maclean, Grafton); Hastings (Wauchope, Port Macquarie) Central Presbytery: Manning (Taree); Hunter (Queens Avenue, Cardiff, Raymond Terrace); Sydney: St Georges, 201a Castlereagh Street, Mount Druitt, Bexley North Southern Presbytery: Geelong (Newcomb), Melbourne - Knox (Wantirna), All Nations (Mulgrave); Carrum Downs; Narre Warren; Ulverstone, Tasmania