The Bishop of Sheffield, the Rt Rev Steven Croft, said the Government proposals on gay marriage represented a "fundamental change" to a "very, very important" social institution.
One in four marriages in England are performed by the Church of England and that proportion is rising at the moment.
In every marriage service the priest begins the service by spelling out what marriage is - a union between one man and one woman with the intention of it being lifelong.
So it is really important to register back to the Government that this is not a minor change, this is a fundamental change to a very, very important social institution.
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