The Australian full-back, who holds a traditional Christian understanding of the issue, replied to a question on Instagram which asked what God's plan was for gay people.
He replied: "HELL...Unless they repent of their sins and turn to God."
Despite deleting the post, an image of his comment has been shared online thousands of times.
A spokesman for his employer, Rugby Australia, told the Sydney Morning Herald that Folau's comments "did not reflect the views" of the organisation.
Folau also received backlash when he publically stated that he wouldn't support the legalisation of gay marriage in Australia's referendum on the issue last year.
At the time, he said: "I love and respect all people for who they are and their opinions. but personally, I will not support gay marriage."
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