A TRADITIONALIST surge is expected in a push for a full ban on gay ministers who are in same-sex relationships today as the Church of Scotland faces its greatest challenge yet on the issue.

The development comes as new Moderator, the Right Rev Lorna Hood, met congregations at the annual Heart and Soul event in Princes Street Gardens. Karen Matheson, lead singer with Gaelic band Capercaille, sang as part of the festival which celebrates Scottish Christianity with music, drama, interviews and seminars.

She said: "There are so many Gaelic songs I could choose to sing that people of all faiths and none can connect with. For every person the song is different and has a different meaning.

"Traditionally, these songs have been prayers to God or asking God for forgiveness or understanding or about how people have had to struggle with changes in life and society."

Mrs Hood, who took over the 12-month post from the Right Rev Albert Bogle last week, joined in and sang along at the festival.

However, events are likely to be less harmonious with revisionists who want ministers such as the Rev Scott Rennie to be treated the same as heterosexual clergy expected to face a strong challenge from their opponents, who it was earlier claimed were braced for defeat.

The liberals were warned the traditionalists were "not giving in and nor do we think we are going to lose" as the Kirk prepared for hours of debate among its 850 ministers and elders at the Kirk's annual gathering at The Mound in Edinburgh.

They are expected to choose between three options, with traditionalists backing the stance of no more ministers in same-sex relationships being appointed, revisionists wanting all clergy to be treated the same and a third so-called "mixed economy" which would allow gay ordination, but with congregations able to decline to appoint a gay minister.

The Rev Mike Goss, minister at Carnoustie and secretary of the evangelical Forward Together movement, said those backing the traditionalist stance are in confident mood.

He said: "I do not think the traditionalists' cause is lost."

The signal came as members of Affirmation Scotland, which supports gay clergy, met in Edinburgh for prayers and discussion before today's debate. The group said it was a crucial time to pray for a "church that courageously affirms and includes everyone".

It is unclear how many congregations or ministers will quit the Kirk if the traditionalists lose. Two congregations and six ministers have already left. Suggestions range from a dozen to more than 50, although a departure on that scale would not be expected to be immediate as any split will be fraught with legal difficulties over property. It would also mean the first full rural congregations leaving, the two previous parishes being in cities – St George's Tron, Glasgow, and Gilcomston South, Aberdeen.

In 2009, a petition gathered more than 8000 signatures against Mr Rennie's appointment and more than 100 congregations joined the Fellowship of Confessing Churches, a movement set up to present the traditionalist standpoint. But there have been divisions on both sides..

The issue of gay clergy has been threatening to split the Kirk since the appointment of Mr Rennie, who is on study leave in the US, to Aberdeen Queen's Cross in 2009.

If the Kirk agrees to gay ordination of ministers it is expected to put a moratorium on recruitment for a year and during that time re-introduce the controversial gagging order on courts, councils and committees from speaking to the press on the issue.

Three options are on the table for the General Assembly of the Church of Scotland to consider today. They are:

l The Traditionalist stance is that gay clergy should be celibate, and no more ministers in same-sex relationships should be appointed.

l The Revisionist position is that active gay clergy should be treated in the same way as heterosexual ministers.

l The third "mixed economy" option aims for both traditionalist and revisionist beliefs and views within the Kirk. Ministers and congregations are opted in to the ordination of ministers in same sex relationships, but a "conscience clause" allows ministers and congregations to opt out.

It is expected counter-motions and amendments will be made during today's debate.

BRIAN DONNELLY