Turner's preferments were mainly due to the favour of the Duke of York, to whom he was chaplain. On 30 December 1664 he was instituted to the rectory of Therfield, in Hertfordshire, succeeding John Barwick. On 17 February 1664-5 he was incorporated at Cambridge, and on 8 May 1666 he was admitted fellow commoner in St John's College, Cambridge, to which the patronage of Peter Gunning, the Regius Professor of Divinity, attracted him. He compounded BD and D.D. at Oxford on 6 July 1669. On 7 December 1669 he was collated to the prebend of Sneating in St Paul's Cathedral. On 11 April 1670 he succeeded Gunning as Master of St John's, Cambridge; he was vice-chancellor in 1678, and resigned his mastership, "because of a faction," at Christmas 1679. In 1683 he became rector of Great Haseley, Oxfordshire, and on 20 July of that year he was installed Dean of Windsor. He was consecrated Bishop of Rochester, at Lambeth on 11 November 1683, holding his deanery in commendam, with the office of Lord High Almoner. On 16 July 1684 he was translated to Ely in succession to Gunning, who had made him one of his literary executors. He preached the sermon at James II's coronation ; in the following July he prepared James Scott, 1st Duke of Monmouth for his execution.
Religious and political controversy
Turner's obligations to James did not prevent him from joining in the petitionary protest of the seven bishops against the king's declaration for liberty of conscience. He also declined the oath of allegiance to William and Mary, and hence incurred suspension on 1 August 1689; his diocese was administered by a commission consisting of Henry Compton, Bishop of London, and William Lloyd, Bishop of St Asaph; on 1 February 1690 he was deposed. He was in correspondence with James; two unsigned letters to James and his queen, dated 31 December 1690, and seized on the arrest of John Aston, are certainly his. He professes to write "in behalf of my elder brother, and the rest of my nearest relations, as well as for myself". A proclamation for his arrest was issued on 5 February 1691, but he kept out of the way. On 24 February 1693 he joined the nonjuring bishops, William Lloyd and Thomas White, in consecrating George Hickes and Thomas Wagstaffe as suffragans of Thetford and Ipswich, the object being to continue a succession in the Jacobite interest. Henry Hyde, 2nd Earl of Clarendon, was present at the ceremony, which took place at White's lodging. In 1694 it was proposed that Turner, who was in easy circumstances, should be invited to St Germains in attendance on James, a proposal which James approved but did not carry out. In December 1696 Turner was arrested, as the nonjuror Samuel Grascome was sought, but then discharged on condition of leaving the country. On 26 December he was rearrested. With John Somers, Baron Somers arguing for him, he survived.
Death and posterity
No more is heard of Turner till his death, which occurred in London on 2 November 1700. He was buried on 5 November in the chancel at Therfield. His intestacy gave all his effects to his daughter Margaret, wife of Richard Gulston of Wyddial Hall, Hertfordshire, thus disappointing the expectation of bequests to St John's College, of which he had already been a benefactor. Turner is an ancestor of Henrietta Euphemia Tindal, a 19th-century poet, who was the great granddaughter of a later Richard Gulston of Wyddial Hall, and of the Tindal-Carill-Worsley family. Besides single sermons Turner published:
Animadversions on a Pamphlet entituled "The Naked Truth".
A portrait of Turner, painted probably by Mary Beale, was transferred from the British Museum to the National Portrait Gallery in 1879. He also figures in the anonymous portrait of the seven bishops in the same gallery.
MacDonogh, Rev. T. M.. Brief Memoirs of Nicholas Ferrar: founder of a Protestant religious establishment at Little Gidding, Huntingdonshire. Chiefly collected from a Narrative by the Right Rev. Dr, Turner, Formerly Lord Bishop of Ely; And now edited, with Additions. Second Edition. London: Jacob Nisbet, 1837.
A sermon preached before Their Majesties K. James II, and Q. Mary, : at their coronation in Westminster-abby, 23 April 1685.