The Reverend Isaac Williams (1802–1865) was a prominent member of the Oxford Movement, a student and disciple of John Keble and, like the other members of the movement, associated with Oxford University. A prolific writer, Williams wrote poetry and prose including the well known Tract: "On Reserve in Communicating Religious Knowledge".
In 1841, Williams had been suggested as John Keble's successor as the professor of poetry at Oxford. Due to furor raised by Newman's Tract XC, and Williams' association with the Oxford Men, the election became a referendum on Tractarianism. The controversy created became so heated that Williams withdrew his name and James Garbett was given the position.