Church of England's stance on gay marriage

Legislating that marriage could be available for gay couples within the next 3 years or would, according to the church of England, damage the institution of marriage. 
http://www.bbc.co.uk/news/uk-18405318The main basis of the argument appears to be the definition of marriage as being between an man and a woman and for procreation. By allowing gay marriage it would undermine the CofE and its "vast" importance to society. 
Yet again, a religious institution fails to move with the times and progress naturally. Rather than being at the forefront of change, leading the world to a better place and potentially bringing more people together, it hangs back, clinging with all its might to outdated notions about what the right thing is to do. The right thing is equality for the legal status of people who chose to share their lives together. It is clear that the sex of the individual is insignificant, it will not damage society nor will it undermine anything for anyone. It merely is an extension of rights to those who are different. There are religious organisations and leaders that support gay marriage (http://www.bbc.co.uk/news/uk-17796511) and they certainly seem to be moving in the right direction. It is a shame the people who issue the statements and policies of the CofE are not progressive enough to embrace the change that will come, and it will, sooner or later.