The Church of England General Synod was today urged to reject plans to introduce blessings for same-sex couples.
The debate over motion GS 2289 is set to continue into Thursday after deliberations ran over the 7pm deadline.
The motion asks Synod to approve the proposals put forward by the House of Bishops in response to Living in Love and Faith (LLF), a process of discernment in the Church of England around the issues of marriage, relationships, sexuality and identity.
It also asks Synod to "lament and repent of the failure of the Church to be welcoming to LGBTQI+ people and the harm that LGBTQI+ people have experienced and continue to experience in the life of the Church".
Moving the motion, the Bishop of London, Sarah Mullally, said that the motion "describes what the change needs to look like for our repentance to have integrity".
Speaking in support, the Archbishop of Canterbury, Justin Welby, said there were "no convenient or easy easy forward" as he asked Synod members to vote with their "Spirit-inspired consciences".
"Each of us will answer to God at the judgement for our decisions on this matter. We are personally responsible," he said.
"I am supporting these resources not, I think, because I'm controlled by culture but because of Scripture, tradition and reason evidenced in the vast work done over the last six years so ably, by so many.
"I may be wrong, of course I may, but I cannot duck the issue anymore than anyone else here."
While many evangelicals have spoken in the lead-up to the debate about their fear of doctrinal change on marriage, the Bishop of Oxford, Steven Croft, admitted to Synod that he was hoping for as much further down the road.
The bishop, who came out in support of same-sex relationships in his Together in Love and Faith paper last November, told Synod his prayer was that the blessings would be "a stepping stone" on the journey to equal marriage in the Church, and that "people in same-sex relationships and those relationships will become more visible".
"That, in turn, I know would change other hearts and minds in the months and years to come," he said.
Bishop Croft went on to say that if the Church of England progresses in this direction, he foresees a "mediated settlement" with Anglicans who hold a traditional view of marriage.
That suggestion was shared by Vaughan Roberts, Rector of St Ebbe's, an evangelical Anglican church in Oxford, who said that the existence of the Anglican Communion was under threat, and asked that a mediated settlement be considered if the Church refuses to affirm its historic teaching.
He told Synod members to think very carefully about the implications as he warned that the approach on offer "will not keep us united but only drive us further apart".
He said, "The doctrine has been clear but now, for the first time, if these proposals proceed, we will be allowing clergy to bless sexual relationships outside of marriage between a man and a woman and that will mean a de facto change in our doctrine, and we will be effectively naming as holy what we, along with the universal Church down the ages - and still the predominant view throughout the world - have always before now called sin," said Roberts.
"Let us be in no doubt whatsoever that that is a very, very serious step to take," he added.
In an impassioned appeal, Christian Concern's Benjamin John said it was "not too late" for the Church to turn back to the "beautiful, wonderful, glorious Gospel".
"These proposals are wrong. They say that Jesus doesn't wash and sanctify you, that you do not need to take up your cross and follow him, that there is no call to holiness, that the truth does not set you free," he said.
"But love rejoices in the truth, it does not rejoice in wrongdoing. Love calls people out of sin and to Christ, snatching them out of the fire with discipline so that their spirits might be saved.
"Please bishops, I plead with you: withdraw the proposals and prayers. Turn from this path that you are on. Fear God, not man. Be the shepherds that God is calling you to be. Protect the sheep entrusted into your care by driving out this teaching that perverts the grace of God into a licence for immorality."
Also speaking against the motion was the Bishop of Lancaster, Jill Duff, who said that introducing same-sex blessings "would be a seismic shift in Christian teaching".
"It would distance LGBTQI+ Christians living faithful, celibate lives [and] it would distance mainstream denominations, never mind the freedom of conscience for other faiths.
"It will be distancing the majority of the Anglican community who seem to be rather silent in our discernment."
The five-hour debate saw Synod reject some 16 amendments to the motion, including a number put forward by Sam Margrave to overturn the proposals.
Another rejected amendment called for an audit across all 42 provinces of the Anglican Communion into the impact of the proposals.
The amendment was proposed by Busola Sodeinde, a Church Commissioner and member of the Holy Trinity Brompton PCC.
She said that the plans threatened to foster "racial injustice, disunity and racial segregation", as well as an "exodus" of ethnically diverse communities from the Church of England.
"We are in danger of shutting our ears, ignoring the 75 per cent of the Anglican Communion who look to the Church of England as their mother church," she said.
Speaking in support of her motion, Folli Olokose, vicar of St Mary Oatlands in the Diocese of Guildford, said that there would be a "ripple effect" across the Anglican Communion and possibly deadly consequences for Christians living in places where there is persecution.
"Our brothers and sisters, not just in Nigeria but in other places around the world where they are in the minority, we are throwing them under the bus," he said.
Olokose added, "We are putting the nail into the coffin of the Anglican Communion and not just a nail; we are burying it, burning its ashes and throwing it to the wind ... Let us consider the cost."
Archbishop Welby teared up as he admitted to being "genuinely torn" by the amendment before rejecting it on a technicality while offering to instruct Bishop Anthony Poggo, Secretary General of the Anglican Communion, to consult with primates.
"I beg you to believe there is nothing in my life or heart or prayers that comes as high as the safety and the flourishing of the people I love in the Anglican Communion, and at the top of that list comes Nigeria," he said.
More amendments will be considered when the debate continues on Thursday morning.