Vincent Nichols, the leader of the Roman Catholic Church in England and Wales, made the comments in an interview with the BBC.
He said there was no mandate to enforce same-sex marriage laws.
He said: "There was no announcement in any party manifesto, no Green Paper, no statement in the Queen's Speech.
"And yet here we are on the verge of primary legislation.
"From a democratic point of view, it's a shambles.
"George Orwell would be proud of that manoeuvre. I think the process is shambolic."
The religious leader claimed that during a "period of listening", those who responded were "7-1 against same-sex marriage".
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Speaking to the congregation at Westminster Cathedral during Christmas Eve mass, Archbishop Nichols said: "Sometimes sexual expression can be without the public bond of the faithfulness of marriage and its ordering to new life.
"Even governments mistakenly promote such patterns of sexual intimacy as objectively to be approved and even encouraged among the young."
The government is confident of getting a Bill, set to be introduced in January, through the Commons and the Lords - however it may have to rely on the Labour Party to secure its passage.
You can read the full text of Archbishop Nichols's homily here.