A school board member in Cobb County picked at a 500-year-old scab just ahead of an important local election, asserting in a social media exchange that Catholics are not Christians.

The comment on Facebook, in reaction to a historical post about Martin Luther, provoked a backlash of both the religious and political kind.

David Banks’ use of a public forum to denounce the Roman Catholic Church comes at a delicate moment for fellow Republican school board member David Chastain, who is running for reelection in a race that could tip control over the board to Democrats.

Some Catholics in Cobb said they found Banks’ post — particularly the part about them not being Christian — to be offensive and bigoted.

“The Roman Catholic Church can not be Christian. More paganism in its beliefs. If Roman Catholics read the Bible,” Banks wrote. “They would realize the false doctrines. Only Jesus Christ is the head of the church.”

Banks did not return calls for comment.

Democrats are trying to wield it against Chastain, who as school board chairman has had to speak for the board about Banks. They say Chastain’s refusal to judge Banks’ words amounts to an endorsement of bigotry.

Chastain told the Marietta Daily Journal that Banks is entitled to his opinions and that they have nothing to do with the school board and its business. He wouldn’t opine about the opinions Banks expressed, and he didn’t return calls for comment from The Atlanta Journal-Constitution.

Banks’ post was in reaction to a former local Republican leader’s post observing the 505th anniversary of Martin Luther’s “Ninety-five Theses.”

Luther’s critique of Roman Catholic teaching, which according to legend he posted on a church door, went viral without the benefit of the internet. It was a catalyst of the 16th-century Protestant Reformation, and preceded centuries of bloody conflict.

“He’s telling me that I’m not included, that I’m not part of Jesus’ way. That’s just fundamentally super offensive,” said Dominic Thomas, a local dad who grew up Catholic but now attends a Unitarian church.

Thomas said he has two boys in Cobb schools that are in Banks’ east Cobb district.

Teri Anulewicz, a Catholic who is the Democratic state representative for central and southern Cobb, said she’s not shocked by Banks’ incendiary religious thoughts given the way he has addressed COVID-19 (reportedly calling a constituent a “mask Nazi” and the disease the “China virus”).

“He just shoots off at the mouth,” Anulewicz said of the longtime board member and current board vice chairman. “I know he’s a bigot. That’s established.” The problem, she said, is that Chastain has not condemned it. “It’s giving people the impression that the board is OK with it.”

National Republican political consultant Heath Garrett, who lives in Cobb, said “unforced errors” ahead of an election are not helpful, but are a bigger deal at the national level.

“While the Democrats may want to make hay with this, I’ve never seen it affect — at this level of politics — the school board member next door,” Garrett said. “Unless the Democrats were to spend a lot of money educating board of education voters in east Cobb, most folks aren’t going to be moved by this when it comes to voting.”

Banks’ post came after former Cobb GOP chairman Jason Shepherd’s Facebook entry about Martin Luther. Shepherd, who attended Catholic school into first grade, said what Banks wrote is “bigoted” because it’s “based on a prejudgment rather than knowing precisely what Catholics believe.”

But Shepherd said he still likes Banks and that most of his critics are not in Banks’ part of the school district, where Shepherd hears he remains popular. “He may be the politically incorrect uncle at Thanksgiving dinner but he’s also the uncle that remembers your birthday and gives you $50,” Shepherd said.