Ann Atkins, a novelist and former actress, who is married to an evangelical vicar, delivered a ferocious blast against what she said was a commemoration of "20 years of gay sex''.
"It is the Church's duty to condemn sin and . . . this we are failing to do. Soon, no doubt, we will have an adulterers' Christian Fellowship, a 'sex before marriage' Christian fellowship. [We] see no reason why the list should ever end unless and until the Church comes back to God's standards of morality," she said.
"A report has just been published . . . which says that candidates for ordination in the Church of England are steadily going down. Surprise surprise.
"If the trumpet give an uncertain sound, who should prepare himself for battle? Sadly, the sound given by the Church of England today is so uncertain you'd never even know it was a trumpet," she concluded.
Such strident certainties are not often heard on Thought for the Day, a slot made famous by the musings of Lionel Blue, the most prominent gay rabbi in England.
The Church's director of communications, The Rev Eric Shegog, has made a director's first complaint to the BBC about the early morning religious slot, describing her talk as "factually inaccurate and containing basic errors.
"To say that a decline in vocations is attributable to the church's position on homosexuality is preposterous.
"We feel that the BBC has made a serious error of judgement in transmitting this Thought for the Day and would welcome an apology."
A spokesman for the BBC said: "Ms Atkins represents one not insubstantial viewpoint within the churches, which believes that the Bible is authoritative in matters of doctrine and morality. Listeners may not agree with her, but she is entitled to her opinion."
The BBC admitted, however, that it had received a "substantial number of complaints from listeners". Not all were wholly serious. Many, according to one insider, protested that there had been far more than 20 years of gay sex for the Lesbian and Gay Christian Movement to celebrate.
Ms Atkins was yesterday unrepentant. "I suppose that a lot of things that Jesus said weren't very tactful, either.
"Everything that we believe has been blurred round the edges, and that means that people lose confidence in the Church's ability to be a fighting force."
Ms Atkins is due to give the Thought For The Day for three more Thursdays.