A leading liberal clergyman in London has defended his right to offer services of thanksgiving after gay weddings and to hold a full Muslim prayer service in his church.

Rev Giles Goddard, vicar of St John's Waterloo, said his aim was to help his church live out the CofE's values in central London.

"It is very much about St John's being a place of welcome," he told Christian Today. "We understand God as a generous God, a God who celebrates love and celebrates life.

He was committed to engaging with the whole community, he added. "We try and make sure we live that out. In that sense we feel very properly Anglican."

St John's recently hosted an "Inclusive Jummah" in partnership with the Inclusive Mosque Initiative. Led by Dr Amina Wadud, it was timed for the run up to International Women's Day last weekend. Dr Wadud is a long-time campaigner for gender justice in Islam.

St John's also offers thanksgivings and dedications to couples after civil marriages, including same-sex marriages, although so far no one has requested such a service.

Mr Goddard told Christian Today that everything his church did was legal and within bishops' guidelines, and in addition, his congregation was growing, and now numbered more than 100 compared to just 60 five years ago.

His liberal ministry has however put him at odds with the influential orthodox evangelical churches in Southwark.

The US conservative evangelical website Stand firm in Faith described the diocese as "gripped in a growing standoff" between the bishop and his evangelical parishes who are said to be increasingly disenchanted with his "Biblical and canonical standards", particularly in the area of human sexuality.

Anglican blogger David Ould has also reported that Southwark is coming under "increasing pressure for its refusal to back away from revisionism. More widely there is a great deal of unhappiness amongst all theological stripes."

Ould compared it to the neighbouring London diocese which is growing.

He said Bishop of Southwark Christopher Chessun recently met with orthodox representatives to discuss the number of partnered gay clergy in senior leadership positions in the diocese. "Jaws were literally dropping during the diocesan conference at the latest senior appointment of someone who is in a same sex relationship," he wrote.

Ould reported that there had even been correspondence with Lambeth Palace and he had seen a reply stating that the Archbishop of Canterbury, Justin Welby, had "set his course on the facilated conversations route."

Ould reported: "It's a war of attrition. Bishops have gone from guardians of the faith to referees ... Since when was that change of role agreed?"

Last month, orthodox clergy in Southwark released a manifesto, the Southwark Declaration, backed by 60 priests, calling on Bishop Chessun to govern his diocese in accordance with the Bible and Canon Law.

In addition, 27 clergy submitted a private letter warning Bishop Chessun of consequences for the diocese if the liberal-catholic trends continue.

The declaration states:

As clergy and lay people in the Diocese of Southwark:

We affirm the divine inspiration of the Holy Scriptures and their supreme authority in all matters of faith and conduct. We affirm with Canon A5 that 'the doctrine of the Church of England is grounded in the Holy Scriptures, and in such teachings of the ancient Fathers and Councils of the Church as are agreeable to the said Scriptures.'

We affirm, with Article XX, that 'it is not lawful for the Church to ordain any thing that is contrary to God's Word written.'

We affirm the teaching of Scripture (Genesis 2.24, Mark 10. 7, Matthew 19.5), the Book of Common Prayer, and Canon B30 ('Of Holy Matrimony') that marriage is the union of one man and one woman for life. We affirm it is the one God-ordained context for sexual intercourse. We affirm resolution 1.10 on human sexuality of the Lambeth Conference (1998).

We call upon all the Bishops, Archdeacons, and the senior staff of the Diocese, alongside all clergy and licensed lay ministers, to affirm these truths, live by them, and to teach in accordance with them.

We call upon the Bishops to appoint to positions of teaching authority only those who hold to these truths in good conscience.

Canon Wendy Robins, spokeswoman for Bishop Chessun, said: "The Bishop of Southwark has received a copy of the declaration. He is grateful for the contribution that conservative evangelicals make to the life of the diocese. As you may be aware there is an opportunity for the whole of the Church of England to discuss these issues through the shared conversations and the Bishop of Southwark welcomes this."