In 1872 he became vicar of St Jude's, Commercial Street, Whitechapel, and in the next year married Henrietta Octavia Rowland, who had been a co-worker with Miss Octavia Hill and was no less ardent a philanthropist than her husband.
In 1875 Arnold Toynbee paid a visit, the first of many, to Whitechapel, and Mr Barnett, who kept in constant touch with Oxford, formed in 1877 a small committee, over which he presided himself, to consider the organization of university extension in London, his chief assistants being Leonard Montefiore, a young Oxford man, and Frederick Rogers, a member of the vellum binders' trade union.
The Barnetts were also associated with the building of model dwellings, with the establishment of the children's country holiday fund and the annual loan exhibitions of fine art at the Whitechapel gallery.
At home a Union for Social Service was formed in 1906, the natural outcome of Thomas Jackson's efforts for the hungry and distressed in Clapton and Whitechapel, and of similar work at St George's Hall, Southwark.
The northern road enters from Stratford and is called Bow Road, Mile End Road, Whitechapel Road and High Street, Whitechapel.