Yet Bishop O’Connor soon became a well-respected figure. He had the Catholic catechism translated into the Tamil language, and in 1837 founded schools for Christian girls in spite of Hindu resistance. In a display of leadership in 1839, he led the other vicars apostolic of the Catholic Church in India in formally ending a schism.
The number of Catholics recorded as resident in Madras on 14th March 1838 was only about 3,000. When O'Connor resigned in 1840 because of ill health, it was reported in 1856 by W.J. Battersby (see bibliography on the previous page) that the Catholics of Madras were “pained to extremity.” As a parting gift, they presented him with a valuable gold and diamond cross, chain and episcopal ring.
He returned to Ireland, was appointed to the Augustinian community at John’s Lane in Dublin, and ministered as an episcopal assistant in the Archdiocese of Dublin. An obituary states that in Dublin between 1842 and his death in 1858 he received 553 persons into the Catholic Church, and rectified 800 marriages that hitherto lacked church approbation. To the Dublin poor whom he assisted, he was known as “the John’s Lane bishop.”
He was on intimate terms with political figures in Ireland such as Daniel O’Connell, Charles Gavan-Duffy, Fr Matthew, and other leaders of the Repeal and the 1848 Movements.
He died in Dublin on 10th July 1867 at the age of eighty-one years, and was interred at Glasnevin Cemetery.