Theobald Mathew (1790–1856) was an Irish Catholic priest and teetotalist reformer, popularly known as Father Mathew. He was born at Thomastown, near Golden, County Tipperary, on 10 October 1790, to James Mathew and his wife Anne, daughter of George Whyte, of Cappaghwhyte.
Of the family of the Earls Landaff (his father, James, was first cousin of Thomas Mathew, father of the first earl),he was a kinsman of the clergyman Arnold Mathew.
Father Mathew visited the United States in 1849, returning in 1851. While there, he found himself at the centre of the Abolitionist debate. Many of his hosts, including John Hughes, the Roman Catholic Archbishop of New York, were anti-abolitionists and wanted assurances that Mathew would not stray outside his remit of battling alcohol consumption. But Mathew had signed a petition (along with 60,000 Irish people, including Daniel O'Connell) encouraging the Irish in the US not to partake in slavery in 1841 during Charles Lenox Remond's tour of Ireland.
In order to avoid upsetting these anti-abolitionist friends in the US, he declined an invitation to publicly condemn chattel slavery, sacrificing his friendship with that movement. He defended his position by pointing out that there was nothing in the scripture that prohibited slavery. He was condemned by many on the abolitionist side, including the former slave and abolitionist Frederick Douglass who had received the pledge from Mathew in Cork in 1845. Douglass felt "grieved, humbled and mortified" by Mathew's decision to ignore slavery while campaigning in the US and "wondered how being a Catholic priest should inhibit him from denouncing the sin of slavery as much as the sin of intemperance." Douglass felt it was his duty to now "denounce and expose the conduct of Father Mathew".