A split has opened in the Church of Ireland over its attitude to the DUP's 'conscience clause'.
An article in tomorrow's Church of Ireland Gazette newspaper has sparked off an angry reaction from a pro-LGBT pressure group.
If passed, the Lagan Valley MLA's Private Members Bill would allow those with strongly-held religious beliefs to refuse to provide certain services.
Mr Dorrian said he would seek amendments to the bill to "ensure it cannot be used to facilitate discrimination against members of the LGBT community".
Rev Dorrian said: "We will certainly encourage a comprehensive conversation around religious and civil freedom in Northern Ireland and I will be affirming the Church of Ireland's position that marriage 'is part of God's creation and a holy mystery in which one man and one woman become one flesh'."
However, Canon Charles Kenny from the Church of Ireland's gay rights group Changing Attitude Ireland said Rev Dorrian's views may not be representative.
The Church of Ireland did not make a formal written response to a consultation process on the bill which ended last Friday.
Rev Kenny said: "I hope that the Rev Dorrian's view is not shared by all members of the Commission or the wider membership of the Church of Ireland."
"This is more Mr Dorrian's views, as he's known as a social conservative, rather than the views of the Church and Society Commission as they have not put out any official response to the DUP over the consultation.
"He seems to be making this an issue between gay people on one hand and Christians on the other.
"And it's not. There are lots and lots of members who do not accept the hardline, fundamentalist, biblical literalistic line that Mr Givan and the DUP has as a whole."
He said that he was dismayed at the anti-gay motivation and tone of the DUP's conscience clause but was heartened by the nearly quarter of a million signatories to an online petition against it.
Last night Mr Dorrian confirmed that the Church and Society Commission had yet not met to discuss its official response, although he and several other Commission members met Mr Givan yesterday.
He said: "With regard to the Ashers Bakery cake I think the vast majority of Christians seem to think that there is mismatch between the Ashers case in relation to the charges being brought against the bakery and what actually happened. The Church of Ireland is very clear that there can be no room for discrimination, but that doesn't mean that there can't be a disagreement about how to interpret the morality of such things."
In 2012, the church's Synod voted to reaffirm its support of traditional marriage between a man and a woman.