He was educated at Eton College and matriculated at Christ Church, Oxford, in July 1829. There he was elected a student in the same year, gained a first class in classics at the Easter examination and graduated Bachelor of Arts in 1833, was Master of Arts
In 1836, and Bachelor of Divinity in 1844. Jelf was ordained in 1834. From 1836 to 1849 he was tutor of Christ Church, and for a time was senior censor.
He was master of the schools, 1839.
Classical examiner, 1840, 1841, 1855, and 1856. Proctor of the university, 1843.
Select preacher, 1855. And classical moderator, 1862, 1863.
As proctor and senior censor he was unpopular, striking the wrong note with undergraduates.
One of the Whitehall preachers from 1846 to 1848, Jelf left Oxford in 1849 to become vicar of Carleton, North Yorkshire, a college living. Here he remained till 1854, when he moved to Caerdeon, near Barmouth, in North Wales. He held no church preferment there, but officiated in a church, Street Philip"s, built on his own property.
lieutenant was consecrated and endowed as a district church in 1875.
A significant court case permitted the use of the English language and opened the way to liturgical anglicisation in predominantly Welsh-speaking areas. In 1857 he delivered the Bampton lectures on The Christian Faith comprehensive and definite.
He devoted much of his time to controversy: attacks on ritualism, confession, and mariolatry. The last few months of Jelf"s life were passed at Hastings, where he died on 18 October 1875.