[2][4] He was ordained in 1886,[5] then embarked on his ecclesiastical career with a curacy at West Wratting, Cambridge diocese, Ely from 1886-1888.
From March 1890 to 1894 he was a tutor at Te Rau Kahikatea Theological College, which had been established in Gisborne by his father, Leonard Williams.
He established Te Rau Press, which published religious texts including Maramataka, a lectionary, from 1899 to 1921.
[2] In 1917 Williams published the fifth edition of A dictionary of the New Zealand language, which updated the work of his father and grandfather.
Williams received honorary doctorates in literature from the Universities of New Zealand (1924) and Cambridge (1925).