The issue of same-sex marriages has divided many European countries, including Britain - where both supporters and opponents of gay marriage are watching developments in the U.S. Supreme Court closely.
Justin Welby, 57, officially became the 105th Archbishop of Canterbury last month under the gothic arches of Britain's 900-year-old Canterbury Cathedral. Already the new head of the Anglican Church is in the eye of the stormy debate over gay marriage. He said the Church should fight against homophobia, but it could not support same-sex marriage.
"The Church of England holds very firmly to the traditional view of marriage, that it is a lifelong union with one man and one woman," he said.
A former Archbishop of Canterbury, Lord Carey, reignited the debate over the Easter weekend, accusing the British prime minister of bowing to 'aggressive secularism' in his backing of same-sex marriage.
Gay rights groups and secular campaigners criticized Lord Carey's intervention.
But the former archbishop's comments were timely, says Canon Chris Sugden of the organization Anglican Mainstream.
"It is very important to see that it is the non-material things that contribute greatly to society's health, in particular the health of the family," he said.
The new head of the Roman Catholic Church, Pope Francis, has in the past spoken out against gay marriage.
Eight European countries recognize same-sex marriage, and several more are debating such legislation.
Teresa Pires married her partner on the day Portugal, a majority Catholic country, signed same-sex marriage into law: June 7, 2010. She says, now everybody knows, at least on paper, they are a family, and that is most important.
The gay marriage debate has divided France. Demonstrations by supporters and opponents in recent months have drawn hundreds of thousands onto the streets.
Frédéric Navarro of the gay rights group Act Up Paris says the law is long overdue. He says with the same-sex marriage law, society is beyond the denigration of homosexuality, and regarding homosexuals as if they are somehow below society.
In June, the U.S. Supreme Court is set to rule on a law that defines marriage as between a man and a woman. Canon Sugden of says Europe is watching closely.
"What has not happened in this country is a debate," he said. "At least in America you have Proposition 8, you have had it on the election tickets. Here, no manifesto proposal, no party has put this forward, it has not been in the Queen's speech. It is very undemocratic."
Sugden predicts the debate could have political implications too, with traditional supporters of the ruling Conservative Party withdrawing their backing for Prime Minister David Cameron.