Costco might already have enough on its plate with Black Friday sales looming, but the store has had another obstacle to contend with: a California pastor who discovered Bibles on sale in the store’s fiction aisle. Costco issued a statement on Wednesday apologizing for the “mislabeling,” and called it a “mistake.”

“Costco’s distributor mislabeled a small percentage of the Bibles, however we take responsibility and should have caught the mistake. We are correcting this with them for future distribution,” the retail behemoth said. “In addition, we are immediately relabeling all mislabeled Bibles. We greatly apologize for this error.”

According to the Los Angeles-based TV station KTLA5, the find was made by Caleb Kaltenbach, a pastor at Discovery Church in Simi Valley, Calif. Kaltenbach told reporters that he stumbled across the Bibles accidentally, while shopping for a gift for his wife. He snapped a photo of one of the stickered Bibles and shared it on Twitter last Friday, with the caption “Hmmmm…….” It quickly caught the attention of members of his congregation and began to spread.

“I was completely offende," Shellie Dungan, a member of Kaltenbach's congregation said. "I believe the Bible is real and it shouldn’t be marked fiction."

Kaltenbach’s tweet quickly sparked a religious debate on the social media platform. “DOES Costco sell The Koran under the genre of "FICTION" I WONDER ???” one Twitter user wrote. “pretty sure they don't sell the Koran. Nice try. You guys are getting worked up over nothing,” another user retorted. “calling historical documentation of the Love between God and Man "FICTION" is NOT NOTHIN ! IT'S INSUTING & PREJUDICE,” the original user wrote back.

“what else is [sic] supposed to be? The world doesn't revolve around your religion,” wrote another. Others took the news site’s Facebook page to further debate the issue.

Kaltenbach appeared on Fox News host Elisabeth Hasselbeck's show on Tuesday, where he said that he chalked up the "fiction" labels to a mistake.

But Kaltenbach says that the incident hasn’t changed feelings about the retailer. In a follow-up tweet on Wednesday he wrote, “Just so everyone knows: I'm not outraged, angry, or stunned. I thought the label at Costco on the Bible was interesting.”

In an interview with ABC News, he added, “I love Costco. I still plan to shop there a lot.”