Traditional Anglican ping, continued in memory of its founder Arlin Adams. My opinon here, I could be wrong, and sometimes I am. But...
Things like this just irk me to no end. Call it what it is.
Civil Partnerships are just that. Partnerships. They happen to be "blessed," if you will, by the government. Partnerships need not be between only a man and wife. They can be between just about anyone: business owners, friends, sibilngs, and yes, even same sex couples. It is a legal partnership that has no need of blessing by the Church. Hence the term Civil in its name.
If it is a marriage, then call it a marriage.
If it is to be blessed by the church, then it is no longer Civil, but Holy. That is, is it not, why marriage is called Holy Matrimony?
Now, if what is really being discussed is indeed Holy Matrimony, then the Church's definition of marriage needs to be taken into account. Genesis never mentions marriage for other than a man and wife for any reason other than that of mate. (2:24 For this reason a man will leave his father and mother and be united to his wife, and they will become one flesh.) In fact, according to Genesis we are to fill the earth with our offspring (1:28 God blessed them (man and woman) and said to them, "Be fruitful and increase in number; fill the earth and subdue it...). So taking that into account, we are not only expected to bear children, we are commanded to bear children.
Can a same sex couple fulfill these two requirements?
A) Same sex couple are not comprised of a male and female. So, no to being man and wife.
B) They cannot bear children of themselves alone. So no to filling the earth with their own offspring.
If they cannot fufill these two God given requirements then their union is not Holy, and cannot be called marriage within the realm of the Church. This definition does not even touch upon the unrepentant sinfulness of a homosexual relationship.