Villanueva says the ad was filmed in the church he and his wife attend, and he was given permission to do so by the church.
But the Archdiocese of Los Angeles released a statement saying it was filmed without its approval, and it does not endorse or participate in political campaign activity.
"The video was filmed without the appropriate approvals of the Archdiocese. Archdiocesan policy prohibits any filming of ads on archdiocesan property for candidates running for office," the statement said. "The Archdiocese, which includes our parishes, schools and ministries, does not endorse or participate in political candidates' campaign activity."
The Villanueva campaign issued a statement saying permission was granted by St. Alphonsus Church, and the campaign was unaware further permissions were required.
The campaign said it reached out to the Archdiocese of Los Angeles and is working to resolve any issues.
The ad showed Villanueva walking alone down the aisle as he's heard in a voiceover praying. The ad closes out with the sheriff saying "Amen" in the voiceover and the message "VOTE ALEX" popping up.