The Archdeacon of Norwich has warned the Church of England risks losing credibility if its General Synod fails to back the introduction of women bishops at a key vote today.

And, despite undergoing chemotherapy for breast cancer, the Ven Jan McFarlane is heading to York for the crucial decision, for fear every vote could be crucial.

Mrs McFarlane was one of the first women to become a priest, 20 years ago, and was so disillusioned when the plan was derailed by just six votes cast by lay members in November 2012, that she considered leaving the church.

As one of four representatives of Norfolk clergy on the General Synod, she has been helping work through the procedure for today's vote.

Having been diagnosed with breast cancer in April, Mrs McFarlane, who is director of communications for the Norwich diocese, and lives in Bracondale, has been working part-time while she undergoes chemotherapy.

But she said: 'I do feel a little bit out of it, but I am definitely going to be there today because I don't want it to be lost by one vote which could have been mine!

'It is a huge day, because everybody realises we cannot turn it down this time. I think those who voted against it last time were stunned by the strength of the reaction not only within the church, but outside it as well.

'Now we have reached the point where 43 of the 44 dioceses have voted in favour of it that, for the General Synod to turn it down, would show it is not in touch and will raise serious questions. 'We know the vast majority wants it to happen and if it doesn't, the Church of England will lose credibility.'

Mrs McFarlane, who last year spent time seconded to the Archbishop of Canterbury, the Most Rev Justin Welby - who is backing the yes vote - has just completed her third round of chemotherapy, following surgery.

She said it was fortunate the vote came at a time when her treatment cycle meant she could make the trip up north.

New, simplified legislation was introduced to the General Synod last year. Mediation and conflict management experts were brought in to help resolve differences between Anglo-Catholics and conservative evangelicals opposed to women's ordination and supporters of women bishops.

It is thought that several people who voted against the legislation two years ago will now vote in favour or abstain. The legislation needs a two thirds majority in each of the houses of the General Synod - bishops, clergy and laity.

The Rt Rev Graham James, Bishop of Norwich, said he hoped the vote would come down in favour of women bishops this time around.

He said: 'I hope that even for those who are, in principle, opposed, this time they will feel that arrangements have been made which don't damage the whole body of the church, but still give them an honoured place within it. 'There's an overwhelming mood for it in the Church of England as a whole, which I hope will be reflected in the General Synod this time.'

Last month saw the Ven Jane Hedges installed as the Dean of Norwich, the first woman to be appointed to the post in the Cathedral's 900-year-history.

The Archbishop of Canterbury has said should there be a yes vote, there was a 'good chance' the first woman bishop would be announced by the end of next year.

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