Pope Francis omitted a potentially controversial sentence when delivering his historic speech to the U.S. Congress on Thursday.

The concise line appears to reference the corrosive nature of money in U.S. politics and would have likely made many of the 500-some lawmakers in attendance uncomfortable, as much of the electorate already believes members of both political parties are far too beholden to special interest groups, reported NPR.

Twenty minutes into the speech, the pope was supposed to say: "If politics must truly be at the service of the human person, it follows that it cannot be a slave to the economy and finance," but the Vatican said he lost his place and accidentally skipped the sentence.

In his prepared text, the line came directly after a brief mention of the Declaration of Independence's passage on self-evident truths. The pope then went on to define politics as "an expression of our compelling need to live as one, in order to build as one the greatest common good: that of a community which sacrifices particular interests in order to share, in justice and peace, its goods, its interests, its social life."

Francis concluded the paragraph with, "I do not underestimate the difficulty that this involves, but I encourage you in this effort," and adhered verbatim to his prepared remarks for the rest of the speech.

American politics is flooded with outside money, especially since the Supreme Court's 2010 Citizens United decision, the Guardian notes. "Lawmakers raise tens of millions of dollars from companies and other interests - especially banks - to help fund their campaigns. Companies also pay lobbyists tens of millions of dollars every year to help sway, mold, and kill proposed legislation to suit their needs," wrote the Guardian's Stephanie Kirchgaessner.

For the 2016 presidential election, Bloomberg estimates that spending by candidates, parties and outside individuals could reach $10 billion.

Last March, the pope - who some have criticized for excessive meddling in politics - denounced political money in his home country of Argentina.

"In the financing of electoral campaigns, many interests get into the mix, and then they send you the bill," Francis reportedly said, according to the Crux.

"Everything needs to be transparent and clean," he added.