After the democratic Vice-Presidential candidate Tim Kaine expressed his prediction that the Catholic Church would alter its teaching on gay marriage, two leading U.S. bishops have issued a joint statement declaring that the Catholic Church’s teaching on marriage as the union of one man and one woman “cannot change.”

Detroit Archbishop Allen H. Vigneron, who chairs of the Bishops’ Committee on Doctrine, and Buffalo Bishop Richard Malone, in charge of the Committee dealing with marriage and family life, issued an official statement Wednesday declaring that any attempt “to redefine the essential meaning of marriage is acting against the Creator.”

The bishops stated that efforts to redefine marriage to include same-sex unions “cannot be morally justified.”

Last weekend Kaine told a roomful of LGBT activists that the Catholic Church’s opposition to same-sex marriage would change, suggesting that the Bible teaches that God approves of homosexuality.

The Virginia senator, who has described himself as a “traditional Catholic,” spoke at the national dinner of the Human Rights Campaign on Saturday, where he acknowledged that his position on gay marriage “is at odds with the current doctrine of the church.”

Nonetheless, Kaine went on to say: “But I think that’s going to change, too. I think that is going to change.”

In defense of his position, Kaine said that his support of homosexual relations is rooted in the teaching of the Bible, and specifically the Book of Genesis.

“I think it’s going to change because my church also teaches me about a Creator, in the first chapter of Genesis, who surveys the entire world, including mankind, and says: It is very good. It is very good,” Kaine said, in an apparent inference that God is pleased with everything that goes on in the world.

While carefully avoiding mentioning Kaine by name, the bishops responded to his arguments point by point, suggesting that his interpretation of Genesis was deeply flawed.

According to “the timeless words of the Book of Genesis,” they said, the “vocation to marriage is written in the very nature of man and woman as they came from the hand of the Creator.”

“The goodness and beautiful diversity of God’s creation does not include those things that are consequences of our sins,” they said.

Moreover, we cause “great harm” to ourselves, to each other, and to the world “when we ignore the moral law given to us by God and inscribed in our very nature,” they added, citing recent teachings by Pope Francis.

Earlier this week, celebrated Christian evangelist Franklin Graham slammed Kaine for his suggestion that the Catholic Church should change its teaching on homosexuality and same-sex marriage.

In a Facebook post, Graham said that “Tim Kaine is hoping that the Catholic Church will turn its back on God’s Word and accept the sinful political whims of our culture.”

“I appreciate the Catholic Church remaining very strong on moral issues through the years, and I pray they will be immovable on the teachings of the Bible,” Graham said.

Follow Thomas D. Williams on Twitter