At the Human Rights Campaign’s national dinner, Sen. Tim Kaine explained how he reconciled his support of marriage equality with Roman Catholic faith. Then he made a bold prediction: that the church will one day follow his lead.

“I think it’s going to change because my church also teaches me about a creator who, in the first chapter of Genesis, surveyed the entire world, including mankind, and said, ‘It is very good,’” said Kaine at the Sept.10 dinner, which he keynoted.

“I want to add: Who am I to challenge God for the beautiful diversity of the human family?” he continued. “I think we’re supposed to celebrate it, not challenge it.”

The answer from Catholic leaders came quickly: nope.

Kaine’s bishop, Francis DiLorenzo of the Richmond diocese, released a statement on Tuesday countering Kaine’s prediction––but without specifically mentioning the vice presidential candidate.

“More than a year after the U.S. Supreme Court’s ruling on marriage, and despite recent statements from the campaign trail, the Catholic Church’s 2000-year-old teaching to the truth about what constitutes marriage remains unchanged and resolute,” the bishop said.

“Marriage is the only institution uniting one man and one woman with each other and with any child who comes from their union,” the statement added. “Redefining marriage furthers no one’s rights, least of all those of children, who should not purposely be deprived of the right to be nurtured and loved by a mother and a father.”

The United States Conference of Catholic Bishops released a statement on Sept. 14 from two of its prominent members––the bishops of Buffalo and Detroit––reaffirming the church’s teaching: that marriage can only exist between a man and a woman.

“The Catholic Church’s teaching on marriage as exclusively the permanent, faithful, and fruitful union of one man and one woman cannot change,” their statement said.

“The attempt to redefine the essential meaning of marriage is acting against the Creator,” they added.

Other Catholic figures also ripped him for the remarks.

“Kaine is simply preaching the ‘gospel’ of another faith—and it isn't the Catholic Faith,” wrote Catholic World Report editor Carl Olson.

And Maureen Ferguson, a senior policy advisor at The Catholic Association, pointed out that Kaine’s hoped-for change won’t happen on Pope Francis’s watch.

“If Sen. Kaine wants to go beyond politics to opine on the theology of the Catholic Church, he should at least consult Pope Francis’ most recent exhortation Amoris Laetitia,” she said in a statement, ‘in which Francis states, ‘There are absolutely no grounds for considering homosexual unions to be in any way similar or even remotely analogous to God’s plan for marriage and family.’”

Kaine, who is a practicing Catholic, didn’t always differ from his church on the marriage issue. When a Massachusetts court decision made it the first state to let same-sex couples marry, in 2003, Kaine released a statement saying marriage “between a man and a woman is the building block of the family and a keystone of our civil society,” and criticizing the ruling. And when he ran for governor of Virginia in 2005, he aired radio ads describing himself as a “conservative on issues of personal responsibility” and saying he opposed gay marriage.

His position since then has changed, and in 2013 he announced he supported marriage rights for same-sex couples. LGBTQ Nation’s John Gallagher described it as a “finger-in-the-wind” approach.

And marriage isn’t the only issue where his positions diverge from the Catholic church’s teachings. Rome is unflinching in its opposition to abortion. And for much of his political career, Kaine took a comparatively moderate stance on the issue, backing a variety of policies––including parental notification for minors seeking abortions––that pro-choice activists oppose. But since becoming Clinton’s running mate, he has suggested he might support a repeal of the Hyde Amendment, which would let taxpayer dollars pay for abortion procedures. For the most part, Catholic leaders are unequivocally opposed to this stance.

It isn’t unusual for Catholic Democrats to face scrutiny as they aim to reconcile their religious beliefs with their party’s stance on abortion rights and same-sex marriage. Catholic leaders regularly criticized Nancy Pelosi for her pro-choice stance. And then-Pope Benedict told her in person to back policies that protect “human life at all stages of its development,” the New York Times reported.

Vice President Joe Biden has also drawn criticism for supporting same-sex marriage. Three bishops criticized him, though not by name, a few days after he officiated a same-sex wedding last month, according to the National Catholic Reporter.

If Kaine stays as outspoken as he’s been about his distaste for Rome’s teachings on marriage, he can expect to face plenty more heat from the bishops. But he’ll have company.