Folau, who was sacked by Rugby Australia (RA) in May for posting controversial comments on social media, described the fires as a "little taste of God's judgement".
Wildfires have raged across eastern Australia in recent weeks destroying hundreds of homes and killing six people.
Speaking to members of Sydney's Truth of Jesus Christ Church on Sunday, the former Wallabies player implied the natural disaster was an act of judgement by God following the nation's recent decision to pass laws on abortion and same-sex marriage.
"God's word says for a man and a woman to be together, one man and one woman in the covenant of marriage to be together.
"Abortion - it's now okay to murder and kill unborn children and they deem that to be okay.
"Look how rapid these bushfires, these droughts, all these things have come in a short period of time, do you think it's a coincidence or not?
"God is speaking to you guys - Australia, you need to repent and take these laws and turn it back into following what is right by God," Folau said.
Australian Prime Minister and Christian, Scott Morrison has condemned Folau's remarks as "appallingly insensitive".
Morrsion told reporters on Monday: "He is a free citizen, he can say whatever he likes but that doesn't mean he can't have regard to the grievance [and] offence this would have caused to the people whose homes have burnt down."
Folau is currently appealing the termination of his multi-million dollar contract with RA, who dismissed him for being in breach of their Professional Players' Code of Conduct after he posted 'hell awaits adulterers, drunks and homosexuals' on his Instagram account.
Folau is seeking up to £5.6 million ($10 million Australian dollars) in damages for unlawful termination on the grounds of religious discrimination.
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