Denny, Sir Edward (1796–1889), MP and hymn-writer, was born 2 October 1796 in Dublin, eldest son of Sir Edward Denny, 3rd baronet, of Tralee Castle, Co. Kerry, and Elizabeth Denny, daughter and heir of Robert Day, MP. Educated at Eton, and later Exeter College, Oxford, he graduated BA in May 1815. He canvassed Kerry county from 1816, but did not contest the county in the 1818 general election; it appears his intention was to put his opponent James Crosbie (d. 1836), MP for Co. Kerry (1801–06, 1812–26), to expense. This bitterness was a legacy of the killing of Sir Barry Denny, 2nd baronet by John Gustavus Crosbie (d. 1797) in a duel in 1794. Instead he became MP for Tralee, the family borough, on 29 June 1818, resigning the seat in May 1819 after voting for catholic relief. He was sheriff of Kerry 1827–8 and succeeded his father as 4th baronet on 1 August 1831. He unsuccessfully contested Tralee in the 1832 and 1835 general elections. He appears to have been a benevolent landlord: although he had an annual income of £13,000, his rents were so low that they were not reduced by the land commissioners in the 1880s.
Living in England – in Somerset from the 1830s – he became an influential member of the Plymouth Brethren sect. He was their leading hymn-writer, writing over forty hymns, many expressing millenarian sentiments, and published in Selection of hymns (1830), Appendix to hymns for the poor of the flesh (1841), and Hymns and poems (1848–70). He also wrote theological works and was especially interested in prophecy. In 1830 he wrote an analysis of ‘dispensational time’ based on the book of Daniel, arguing that the world followed a seventy-week cycle. In 1833 he attended a conference at Powerscourt, Co. Wicklow, on prophetic studies.
He died 13 June 1889, unmarried. His brother Anthony (1807–90), a clergyman, was also involved in the evangelical revival movement.