A Statistics Canada study of interreligious unions found that as of 2001 Canada had 2.7 million interfaith marriages, or 19 per cent of Canada's 14.1 million couples. That's up from 15 per cent of couples in 1981.

More than half of the mixed faith unions are all-Christian pairings of Catholics with Protestants: 9.6 per cent of Canadian couples in 2001, up from 8.6 per cent in 1981.

The big jump in half-Catholic marriages is the pairing of Catholics with people of no religion. Since 1991 the number of Catholic-no religion unions has increased 52 per cent. This reflects a big increase in the number of Canadians who claim no religion — 17 per cent in 2001 compared with seven per cent in 1981.

But as the country becomes more culturally and religiously diverse the number of mixed marriages in all categories has increased. While more than 84 per cent of Catholics are married to Catholics, the Statistics Canada study released in November shows that the younger and more urban the couple the more likely they are to be an interfaith couple.

Social worker Clint Tyler's job with Catholic Family Services is to get young couples in Toronto to think out loud about their impending marriage. Out of every marriage preparation class of 30 couples Tyler said he usually comes across two or three who are interfaith.

Tyler asks them, "Why marry in a church? How is this going to be reflected in your daily life? Is faith entering into your marriage?"

But the big question is about children.

"When you say 'both options,' it doesn't work that way," Tyler said. "I don't think I know of one couple I've ever heard of who actually raised a child with both options."

About one in five couples who start a Catholic marriage preparation class decide against marriage, said Tyler.

"We help to define a Catholic vision of a marriage which includes fidelity, includes openness to children, includes a covenant for a lifetime and it's based upon a faith. We get people to define their vision of a marriage and see — how does it fit?"

When Pat and Yokan Persaud got married 36 years ago, where religion fit in was a bit undefined. A Hindu from Guyana, Yokan agreed that the children should be raised Catholic. Now that his children are grown he sometimes wishes he had been able to pass on more of his faith and traditions.

"At the time when we got married I don't think we were thinking religiously. I mean, I grew up in a Christian environment where Catholics went to church on Sunday and that was the end of being Catholic," said Pat.

As their two girls and two boys grew up, the kids' attachment to the church varied according to their individual personalities, said Pat. They attended Catholic schools, where two were confirmed and two chose not to be.

"I left the Catholic Church for a while because when I was working, I was raising the kids, I was trying to take them to church, and I was usually doing that alone and I found that very, very difficult," said Pat. "Sometimes it was just a real struggle to take four children (to church)."

Once the children were grown, Pat found her way back to the church. She's almost finished a Master of Divinity at the University of Toronto's Regis College, and she's hoping to find a way of putting it to use in a church-based social justice project. It's a change of direction the Persaud kids don't necessarily understand.

"To some degree, they think I'm a little odd," she said.

The idea of marriages that produce three out of four children with a weak attachment to their religion is the kind of thing that gives the Jewish community nightmares, said Rabbi Sean Gorman of Beth Tzedec (Orthodox) Synagogue.

"The end result of that is non-existence," he said. "What happens to the next generation? There is no next generation."

Among married Jews, 82.6 per cent are married to other Jews and six per cent are married to Catholics. In 1981 only nine per cent of Jewish couples were interfaith, compared with 17 per cent today.

Most rabbis, whether Orthodox, Reform or Conservative, will not officiate at mixed-faith weddings. Gorman said he doesn't know a rabbi who would buy the idea that you can raise children with a choice of two religions and let them decide when they are older.

"Giving them a choice means that we're putting the responsibility for our own tepid connection on our children. You can't do it," Gorman said.

Because Canadian Muslims tend to be newer immigrants, there's much less tendency to seek marriage outside the community. Just over 91 per cent of married Muslims are married to other Muslims.

Even so, Muslims have the same worries about the next generation that Catholics and Jews have, said Shabir Aly, Imam of the Islamic Information Centre.

"These are practical issues," he said. "How will you live together? How will you as a person maintain your own faith? How will you transmit that faith to your children? Entering into a mixed marriage compromises your objectives in this way. There's a mixing of two different objectives."

Islamic legal scholars have concluded that a Muslim man may marry "people of the book," usually interpreted to mean Christians and Jews though sometimes Hindus are included in the category of religions with a scripture. Women are forbidden to marry outside the faith, according to the legal tradition.

But the legal interpretations are based on practicalities. "There is no real theological barrier," said Aly.

When it comes to theology, the Catholics have a question to ask before mixed marriages ever enter the picture, said Tyler.

"How many couples want a spiritual, a sacramental marriage?"

Though they may not be closely attached to the Catholic Church, Pat Persaud believes religion matters a lot to her kids.

"My two boys will argue religion and argue all sorts of ideas about faith. Especially the younger, he has all sorts of ideas about faith and investigates everything. But I don't think he's decided on anything," she said.

The Persauds believe that that sort of religious searching and uncertainty is more a product of the times than a mixed marriage.