The vicar from 1842 to 1892 was Thomas Chamberlain (later founder of St Edward's School), a firm believer in the Tractarian movement, who introduced daily services as well as such ritualist practices as altar candles and the wearing of Eucharistic vestments – the latter causing him to be rebuked by Bishop Wilberforce in 1855. Many of the leaders of the Oxford Movement, including Edward Bouverie Pusey, Henry Parry Liddon, John Mason Neale, Charles Fuge Lowder and Edward King preached at the church. In the early days of the movement, Anglo-Catholicism was closely associated with St Thomas'. In 1847 Chamberlain founded the Community of St Thomas Martyr, which was devoted to the assistance of the poor of the parish, by now heavily slumland; this sisterhood remained active until 1958. The convent buildings for it were built in 1886, but have since been demolished. In 1846 the north aisle and vestry were demolished and a new aisle of five bays with a vestry at its west end was built in its place. The blocked tower arch and two blocked windows in the chancel were opened and a new chancel arch was built.