"Win, lose, or draw," he said, "starting from scratch two months ago, the campaign for marriage in my country has mobilized thousands of new activists; and created a network that could be deployed to defend Western civilization more broadly and the Judeo-Christian ethic against all that's been undermining it."
These newly activated citizens will be crucial in fighting other challenges to Australian society, such as an effort to legalize assisted suicide in Victoria and a push for gender ideology in schools, he said.
"We need more standard bearers, at every level, because a majority that stays silent soon becomes a minority."
Ultimately, Abbott sees the push to redefine marriage as part of a broader ailment affecting much of Western society.
"Campaigns for same-sex marriage and the like are a consequence of our civilizational self-doubt and the collapse of cultural self-confidence," he said, adding that until Western nations address this underlying question, additional challenges to Christian values will continue to arise.
Michael Farris, president of ADF, agreed, warning that a broader process of religious freedom erosion is at work.
In the two years since the Supreme Court unilaterally redefined marriage for the United States, Farris said, "we have seen individuals and institutions increasingly come under fire simply for trying to live their lives, run their businesses, and operate their ministries consistent with the millennia-old belief, shared by millions of people around the world, that marriage is a sacred union between one man and one woman."
These individuals are not bigots, but "people of sincerely-held religious belief attempting to find their way as entrepreneurs and artists in a new legal landscape," he continued.
Leading up to the redefinition of marriage in the U.S., "proponents of same-sex marriage quelled fears that redefining marriage would threaten rights of conscience by repeatedly promising that same-sex marriage would not infringe on these fundamental rights," Farris said.
"Now, Australians are being told the same falsehood."
In the final days of voting, Abbott warned his fellow Australians to carefully consider the broad consequences of redefining an age-old institution that is so foundational for society.
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"This is a decisive vote," he told CNA, "and it is, one way or another, a watershed moment in the life of our country."
Michelle La Rosa is deputy editor-in-chief of Catholic News Agency. She has worked for CNA since 2011. She studied political philosophy and journalism at the University of Dallas.