People have long found inspiration and insight in the Bible but never a recipe for chicken Parmesan, at least not on Chris Hudson’s watch.

His proofreading company, devoted to checking Bibles before publication, has kept items such as a chicken Parmesan recipe out of Scripture — not because it’s not a heavenly dish but because it isn’t what editors intended for a study Bible’s footnotes, Mr. Hudson said.

“Someone was on a lunch break, they copied a recipe, and then when they got back to their computer, they inadvertently hit the shortcut key for paste,” Mr. Hudson said. “When we got the proofs to review, there’s a full recipe in there for chicken Parmesan.”

Mr. Hudson is president of Peachtree Proofreading Services, which recently noted that it had a critical hand in the distribution of 1 billion Bibles. Some are straightforward renderings of biblical text; others are “study” editions with commentary, explanatory notes and other aids requiring review, lest a recipe or shopping list creep in.

The firm was founded as Peachtree Editorial Services in 1981 and is based in Peachtree City, Georgia. Peachtree says it proofreads roughly 80% of the English Protestant Bibles published in the United States and serves publishers worldwide. It also proofreads many Catholic Bibles and reviewed Scriptures in 12 other languages last year.

Sussing out errant recipes is but one part of the process, Mr. Hudson said.

“I think we check 300,000 items in any Bible that we work on,” he said. “There’s lots of little things, [like] when we can get a sensational thing like a chicken Parmesan recipe. It makes a great anecdote, but it’s just an example of the kinds of things that a human being can introduce.”

Proofreading is vital in publishing, but errors in printing the Scriptures can echo through the centuries. In 1631, British royal printers Robert Barker and Martin Lucas released an edition of the King James Bible in which the word “not” was omitted from the Seventh Commandment (Exodus 20:14), making the verse read, “Thou shalt commit adultery.”

For that mistake and other alleged transgressions, the pair lost their royal license and were fined £300, approximately $64,096 in today’s currency. Although the edition was recalled and supposedly destroyed, at least 15 copies survived and are in museum and library collections. The tale of the so-called Wicked Bible has remained a part of Bible printing lore ever since.

“If you’re reading a novel and you find a typo, you get very proud of yourself, like, ‘Oh, we found a typo,’ and show it to your friends,” Mr. Hudson said. “But when people find a mistake in their Bible, it is distracting, that when they sat down to read the Bible to find God’s message, now they’re fixated on something else.”

Unlike in the 1600s, when movable type and perhaps an absent-minded compositor led to that infamous omission, today’s Bible printing is a computer-based process. Most publishers use Adobe Corp.’s InDesign page layout software, and the text is flowed into the page layouts.

With Scripture text running from 727,969 words for the New International Version to 783,137 words for the King James Version, mistakes can happen, the proofreading firm executive said.

“Because it’s operated by human beings, there’s always a chance that someone will use a ‘shortcut’ keystroke and end up deleting words or adding words,” Mr. Hudson said. “So missing text is always the greatest fear.”

Another worry is formatting errors, particularly among the Bible’s poetic books such as Psalms. He noted that the New International Version contains 20,000 lines of poetry, with indentations in varying spots.

“You have poetry at one level, then another level,” he said. “Those are translation decisions that if someone puts an indent at a certain place, it’s because the translator said, ‘This is a primary thought, this is a secondary thought.’ If you invert them, it changes the meaning. And so those are sometimes the kind of mistakes we find where formatting is off.”

An advantage of computer-based layout is that once a file has been edited and proofread, it can be “locked” as a PDF, which in theory cannot be altered.

“Once something’s locked in a PDF, it’s not supposed to change,” Mr. Hudson said. “Sometimes it still does, but generally, PDFs are fairly safe.”

Automation has also helped the proofreading process. Even a decade ago, humans inspected every line and every word of a publishing file, Mr. Hudson said. Today, software tools help the firm’s proofreaders “make sure that what’s on every page is supposed to be on every page.”

Clint Arnold, a New Testament professor at Biola University and a former dean of its Talbot School of Theology, said getting the Bible’s text right is essential.

“It’s absolutely critically important for it to be correct because you don’t want people running out and committing adultery because they have read something that was inaccurate,” Mr. Arnold said.

The notion of ensuring a Scripture version is correct is hardly new, he said. Although slight variations have been made in ancient manuscripts over the centuries, the Bible as a whole has “been transmitted in an amazingly well-preserved form.”

Those ancient scribes have a linear connection to today’s proofreaders, Mr. Arnold said.

“The scribes that were carefully guarding the Hebrew text were the proofreaders themselves. I think today what we have is the presses, the publishers doing their own proofing,” he said.

Mr. Arnold noted his work on the English Standard Version’s translation oversight committee, where he reviews manuscripts and flags errors or discrepancies for others to review. He said the work doesn’t stop there.

“There’s editorial processes of sub-editors within the publisher itself that are editing it, and it sounds like there are these specialized groups outside that are contracting themselves. So it seems like there are multiple checks along the way for errors to be caught,” he said.

At Peachtree, the system of multiple checks has been in place for decades. The proofreading is based on a system developed in the 1960s by Mildred Tripp, a Bible proofreader for Oxford University Press. She and her husband, Frederick, sold the method to Doug and June Gunden, who formed Peachtree and refined the method into a systematic team approach to proofreading.