Traditionalists opposed to the appointment of gay ministers are planning a campaign of non-co-operation with the Kirk establishment, to deny the Church of Scotland hundreds of thousands of pounds in revenue.

The move is in retaliation against Saturday night’s vote at the General Assembly of the Church of Scotland to uphold the decision of Aberdeen Presbytery to appoint the Rev Scott Rennie to Queen’s Cross parish church, by 326 vote to 267. There were more than 250 abstentions, leaving Mr Rennie, a divorced father who lives with his male partner, admitting that the issue still had to be discussed further by the Church.

Mr Rennie, 37, who served on the Church of Scotland human sexuality taskforce two years ago, said that there were tens of gay ministers already working in the Church, who were afraid of coming out.

“Two gay minsters came to talk [to the taskforce] under anonymity. It's awful that people feel they have to have anonymity before they are free to talk,” he said. “There are issues here for the Church. A space has to be found for gay Christians to have their voices heard. You can’t have an open debate about sexuality if one party feels it is unsafe to talk.”

Evangelical commissioners were aghast at the result of Saturday’s vote in support of Mr Rennie’s appointment, which followed more than four hours of fierce debate. Many felt that proceedings had been rigged by their highly organised liberal opponents on the first day of the General Assembly, it having been ensured that a scheduled debate on the primacy of heterosexual marriage was held only after Mr Rennie’s position was ratified.

That overture (motion) on the sanctity of marriage, proposed by the traditionalist Presbytery of Lochcarron and Skye, will be debated today. Already, a number of counter-motions and amendments have been tabled by liberals which, their opponents fear, could see matters of sexual morality swept under the carpet and considered for a year or more by a Kirk commission, rather than debated on the floor of the Assembly Hall in Edinburgh.

Despite their defeat, evangelical leaders made clear that rather than quit the Church, they intended to fight their corner. They claim that their congregations are among the largest in the Kirk, and simply through the collection plate provide a substantial income stream which can be denied to the church authorities.

The impact of a freeze on collection contributions would be big. A petition against Mr Rennie’s appointment gained the signatures of 272 serving parish ministers, among the 964 listed in Scotland. Evangelicals say that their congregations are among the biggest, from a church membership of less than 500,000. The largest congregations can generate more than £100,000 per annum, up to two thirds being paid over to the church authorities.

The evangelical minsters the Rev David Court, of New Restalrig Church, Edinburgh, and the Rev William Philip, of St George’s-Tron, Glasgow, gave warning in a joint statment of the battles to come: “The General Assembly has shown itself to be seriously out of touch with its grassroots in the churches. But it should remember that these are the people who have — hitherto, at least — kept a creaking denomination afloat financially. There will be a great deal less willingness to do that from now on,” they said.

“People are not obliged to give,” added the Rev Richard Buckley, of Forward Together, a leading evangelical organisation. “As far as we are concerned the Church has sent out a wrong message about Christian morality. God has revealed the truth and . . . the Word of God stands for ever.”

Dr James Simpson, one of three former Moderators of the Church of Scotland who during the debate spoke up for Mr Rennie’s appointment, warned that “some of the bitterest debates in church history begin with the words ‘Scripture says’.” Mr Rennie agreed. “There is no one reading of Scripture that falls from the skies. One of the great myths in the debate about sexuality is that one of the parties believes the Bible and the other does not. It is a caricature,” he said.

Mr Rennie’s appointment was warmly welcomed by Richard Baker, the Labour MSP for North East Scotland. A spokesman for Alex Salmond said: “The First Minister is pleased that the debate was conducted in good spirit and in an atmosphere of mutual understanding.”