Long-standing divisions over human sexuality have "cast a shadow" over the Church of England's Christian witness, the Bishop of London told General Synod on Monday. 

The Church of England's parliamentary body is meeting this week in London to discuss deeply divisive proposals to permit same-sex blessings. 

In a presentation to Synod, Bishop Sarah Mullally said that "these particular disagreements mar our life together, tarnish our reputation in the world we are called to serve, and distract from God's mission".

"They are a source of discouragement and doubt for us in the Church, dragging us away from the 'love, joy and celebration of our common humanity' that the gospel calls us to; they cast a shadow over our witness to Christ, the good news of salvation and redemption that we long to embody and declare," she said. 

Further on in her presentation, the bishop said that LGBT people had been treated "inhumanely" by the Church and that the proposals on the table would address the "urgent necessity for pastoral change" towards same-sex couples "without changing the Church's doctrine of holy matrimony".

"That is because they do not set the couple's relationship in the context of a biblical and theological understanding of marriage and they do not use any of the liturgical material of the Church of England's authorised services of marriage," she said.

Bishop Mullally said that she and the other bishops had received "countless" impassioned letters and emails expressing "seemingly opposing views in the name of Christ" and that it appeared that God was calling the Church to "live with our disagreements". 

"For some unfathomable reason, God, it seems, has allowed us to continue to disagree – disappointingly refusing to engineer a Damascus road experience for one side or the other, either in the Church of England or across the Anglican Communion," she said. 

Bishop Mullally said the question for the Church was how to live with their disagreements "without causing each other so much pain and bringing the Church into humiliating disrepute". 

The plans to bless same-sex couples have been proposed by the bishops on the back of feedback from the Living in Love and Faith (LLF) discernment process on the issues of marriage, relationships, sexuality and identity.

The Bishop of London was chair of the LLF Next Steps Group of bishops who were tasked with formulating proposals to take the Church forward.

Evangelicals have responded to the proposals for same-sex blessings with concerns about their future in the Church of England. Some have expressed the fear that it is only a matter of time before the Church changes its doctrine on marriage as a lifelong union between a man and a woman.

Ahead of a major debate on the proposals on Wednesday, Bishop Mullally said she did not want the Church to split over this issue.

"To separate, to walk apart would impoverish the Church of England," she said.

"The costlier and more narrow way is to walk together, to bear with one another, to suffer the discomfort of our diversity and difference within the body of Christ, to suffer being misunderstood and perhaps even reviled for refusing to say to a fellow follower of Christ – 'I don't need you'."