Chris Sugden, of the conservative group Anglican Mainstream, told Christian Today: "Nothing in the letter gives any reason for departing from the historic and time-tested teaching of the church on man-woman marriage. What the church and its mission needs now is an evidence-based approach to the actual pastoral care afforded to those with same-sex attraction in the church.

Bishop Chamberlain says he obeys Church guidelines which say gay clergy must remain celibate.

The archbishop also said: "His appointment as Bishop of Grantham was made on the basis of his skills and calling to serve the church in the Diocese of Lincoln.

"He lives within the Bishops' guidelines and his sexuality is completely irrelevant to his office."

'Not secret'

The advance publicity notes that there will be "an increase in marginalisation, irrelevance and disengagement" of the new Christian church if it maintains its strict and counter-cultural code of sexual ethics. "There is widespread acceptance and normalisation of a great variety of sexual practices across the Roman Empire and the near East. Christians and Jews who still cling to an outdated and unworkable model are simply not engaging theologically or missiologically.

Other increasingly influential voices would say "yes" to the first question, but "no" to the second. Default orthodoxy is not conducive for church survival in the 21st century. The majority of those who call themselves "C of E" in our country are not evangelical, the argument goes; they are embarrassed by enthusiastic religion, they do not believe many biblical theological dogmas or traditional teaching on sexuality.