Henry (afterwards Cardinal) Newman, he wrote in the ‘British Critic’ for April 1840 a review of Ward's translation of ‘The Statutes of Magdalen College, Oxford,’ published separately later on, 8vo. In 1840 Hope was junior counsel on behalf of the deans and chapters petitioning against the Ecclesiastical Duties and Revenues Bill, and when on 24 July the bill was brought on for second reading in the House of Lords, he argued with such masterly effect before a full house, in a speech of three hours' duration, that Lord Brougham exclaimed at its close, ‘That young man's fortune is made!’ (see Lords' Journals, lxxii. 551 and Hansard). On 25 Aug. 1840 Hope was appointed chancellor of Salisbury by the bishop, Dr. Denison.
Hope meanwhile engaged privately with a brother-barrister and an intimate friend, Edward Lowth Badeley [q. v.], in much charitable and religious work. Between 1840 and 1843 he helped to found Trinity College at Glenalmond in Perthshire, for the education of the Scottish episcopalian clergy. He was in Italy with Badeley from 21 Sept. 1840 to May 1841. He then visited many religious houses, and examined at Rome the general organisation of the holy see. Upon his return to England the Oxford Tractarian movement was at its height. Hope at once became one of its most advanced promoters, and Newman's confidential friend and adviser. His own part in the controversy is best indicated in his published correspondence with the members of the Thurn family and with his two friends Badeley and Mr. Gladstone. Upon the establishment of the Anglo-Prussian protestant see of Jerusalem in the winter of 1841, Hope issued an emphatic protest in a pamphlet entitled ‘The Bishopric of the United Church of England and Ireland at Jerusalem, considered in a Letter to a Friend’ (second and revised edition, 13 May 1842, 8vo). Henceforth he alienated himself from the church of England. On 10 Feb. 1845 he resigned his chancellorship of the diocese of Salisbury. The Gorham trial and judgment of 1849–50 and the popular agitation roused by the creation of the catholic hierarchy of Westminster (30 Sept. 1850) finally induced him to join the Roman catholic church. He was received, together with his friend Archdeacon (now Cardinal-Archbishop) Manning, by Father Brownbill, S.J., at Farm Street, on 6 April 1851. As Newman's adviser he managed the defence in the libel action Achilli v. Newman, 31 Jan. 1852, and in 1855 the negotiations which led to Newman's acceptance of the rectorship of the Catholic University of Ireland.
As early as 1838 Hope was engaged on a Scottish railway bill, the kind of practice in which he afterwards became supreme. But from 1841 to 1843 he practised occasionally in the ecclesiastical courts, and it was not until 1843 that he began to work in earnest as a parliamentary barrister. Thenceforward his practice advanced rapidly. In 1844 he was offered eight or nine general retainers. From 1845 onwards he made a gigantic income, and left all rivals far behind. In April 1849 he was made queen's counsel, with a patent of precedence. He became standing counsel to nearly every railway company in the United Kingdom, and his activity before railway committees largely helped to fix railway law. In one year the London and North-Western Company had twenty-five bills in parliament, and Hope-Scott had charge of them all (Mewburn, Larchfield Diary, p. 170). When he retired from the profession in 1870 he held one hundred general retainers. He often conducted simultaneously several important cases, and always inspired his clients with the fullest confidence. The strain thus put upon his anything but vigorous constitution probably shortened his life. Before a parliamentary committee he was always calm, genial, and unembarrassed, and his influence with the members of the committee was greatly enhanced by his commanding presence and his easy and dignified manners. His tact enabled him, as it seemed, to read intuitively the thoughts of those before whom he was pleading, and to steer his course accordingly. Mr. Gladstone termed him ‘the most winning person of his day.’ Lord Blachford referred to his ‘flexible persuasiveness.’
On 19 Aug. 1847 Hope married Charlotte Harriet Jane Lockhart, only daughter of John Gibson Lockhart, editor of the ‘Quarterly,’ and grand-daughter of Sir Walter Scott. In August 1848 he became the tenant of Abbotsford, which he rented from his wife's brother, Walter Lockhart-Scott. His wife became a catholic soon after his own conversion. Lockhart-Scott, a young cornet of dragoons, died unmarried at the Cape on 10 Jan. 1853, and Hope thus became, in right of his wife, the possessor of Abbotsford. He thereupon assumed the surname of Hope-Scott. In 1855 he bought for 24,000l. the estate of Dorlin (of nine thousand acres), near Loch Shiel, on the west coast of Inverness-shire. There he built a new house, and between 1855 and 1857 added a new wing to Abbotsford. He sold Dorlin in 1871 to Edward George Fitzalan Howard, baron Howard of Glossop [q. v.], for nearly 40,000l. At the height of his professional success he suffered heavy domestic affliction. His wife died in child-bed on 26 Oct. 1858, the new-born child on 3 Dec.,
