Wiseman's researches appeared under the title ‘Horæ Syriacæ, seu Commentationes et Anecdota res vel Litteras Syriacas spectantia, tomus i.,’ and it at once won him a European reputation among oriental scholars, although his interpretation of some Syriac texts were controverted by Samuel Lee (1783–1852) [q. v.] In this work he first described the Syriac version known as the Karkaphensian Codex of the Old Testament, which was preserved in the Vatican library. At the time that he was engaged in these researches he suffered the only temptation, according to his own account, of his life, from ‘venomous suggestions of a fiend-like infidelity,’ but the trial proved temporary and never recurred.
In October of the year in which Wiseman's ‘Horæ Syriacæ’ was published, Leo XII nominated him professor supernumerary in the two chairs of Hebrew and Syro-Chaldaic in the Roman Archigymnasium of the Sapienza, with the provisional assignment of one hundred scudi until the chairs fell vacant.
Meanwhile, in November 1827, Wiseman became vice-rector of the English College, and next year was appointed rector upon the election of Gradwell by propaganda (19 May 1828) as coadjutor to Bishop James Yorke Bramston [q. v.] He held the office of rector for twelve years, and the English College under his guidance enjoyed a new era of activity. He welcomed and entertained a throng of celebrated persons. He won high reputation as a preacher, and Leo XII appointed him special English preacher at Rome. In 1833 John Henry Newman [q. v.] came with Richard Hurrell Froude [q. v.] to consult Wiseman, hitherto a stranger to them both, as to the course they ought to pursue in the spiritual crisis through which the Anglican church was passing.
During the Lent of 1835 Wiseman delivered in the drawing-room of Cardinal Thomas Weld [q. v.] in the Palazzo Odescalchi a course of twelve lectures chiefly dealing with geology, ‘On the Connection between Science and Revealed Religion.’ In the following year the lectures were published in two volumes, and awakened widespread interest and much discussion. The book is a powerful exposition and defence of the orthodox position, and has been repeatedly reissued. A French translation appeared in 1841, and it is included in Migne's ‘Démonstrations Évangéliques’ (1843–53).
Later in 1835 Wiseman returned to England. He had arranged to exchange duties for a twelvemonth with the Abbate Baldaconni of the Sardinian embassy chapel in Lincoln's Inn Fields. In December 1835 he began a course of ‘Lectures on the Principal Doctrines and Practices of the Catholic Church’ at the Sardinian embassy chapel, which he repeated at the request of Bishop Bramston in the Advent and Lent of the following year at St. Mary's, Moorfields. These lectures were published in 1826, and excited much public attention, not only in England but in France and America. Lord Brougham was conspicuous among Wiseman's hearers when they were first delivered. In May 1836, in association with Daniel O'Connell and Michael Joseph Quin [q. v.], Wiseman founded under his own direction a catholic quarterly magazine, with the title of the ‘Dublin Review.’ Quin was the first editor. Outside catholic circles Wiseman's literary abilities were fully recognised, and he was invited to write the article on the catholic church in the ‘Penny Cyclopædia.’
In October 1836 Wiseman returned to the English College in Rome. During the following Lent he published ‘Four Lectures on the Offices and Ceremonies of Holy Week, as performed in the Papal Chapels,’ and delivered at the college ‘Eight Lectures on the Body and Blood of Our Lord in the Blessed Eucharist,’ London, 1836, 8vo. Thomas Turton [q. v.] assailed Wiseman's treatment of the last subject, and Wiseman retorted to him and other critics in a published ‘Reply’ (1839).
By Wiseman's advice Gregory XVI increased the number of vicars-apostolic in England in 1839, and in the following summer Wiseman was appointed coadjutor to Dr. Walsh, the vicar-apostolic of the Midland district, but was almost immediately transferred to the newly created central district. On 8 June 1840 he was consecrated the bishop of Melipotamus in partibus by Cardinal Fransoni in the chapel of the English College at Rome, and was also appointed president of Oscott College. He took up his duties there on 16 Sept. 1840. The Oxford movement was at the time in full progress, and Wiseman's writings and actions largely influenced its development. His article in the ‘Dublin Review’ on ‘St. Augustine and the Donatists’ was pronounced by Newman ‘the first real hit from Romanism.’ Preaching at Derby, Wiseman argued that ‘there is a natural growth in every institution,’ and defined the position of the Roman church in much the same manner as Newman in his ‘Essay on Development.’ In February 1841 ‘Tract XC’ was published. Later in the year Wiseman addressed a published ‘Letter’ to Newman, besides contributing several papers on the illogical position of the tractarians to the ‘Dublin Review;’ these were collected
