Republican presidential candidate Ben Carson said last week that allowing gay couples to marry would lead to plural marriages.

Carson made his comments during an interview with conservative radio host Eric Metaxas.

The retired neurosurgeon told Metaxas that he's a “very reasonable and tolerant person” and has “nothing against gay people whatsoever” before claiming that the unions of gay couples “negate the word of God.”

“If you change the definition of marriage for one group, what do you have for the next group that comes along and want it changed?” Carson asked. “Can you say, 'Oh no, we're just changing it for one group and it'll be this way forever.' How is that fair? It just doesn't make sense.”

Polygamy, Carson continued, is “the natural next question. And on it goes from there.”

“If you can do that with one part of the word of God, you can do it with the rest of it too,” Carson said. “Toss the whole thing in the garbage.”

After he was criticized in June for claiming that being gay is a choice because prison can make a person gay, Carson vowed to no longer discuss gay rights.