Miles was ordained deacon on 20 September 1874 by John Fielder Mackarness, Bishop of Oxford, and was curate of Banbury (1874–1876).
Bishop Allan Becher Webb established the St Cyprian's Theological College in a building in St George's Street, Bloemfontein, in 1876, in the hopes of addressing some the needs of the still new, isolated, poor and sparsely populated Diocese of Bloemfontein.
Miles was recruited due to his Cuddesden connections to serve here as Theological Tutor and was Warden of the College from 1877–1882.
[1] Whilst at the college, Miles also served as rector of St Cyprian's Church in Kimberley from 1881–1882.
Miles also served from 1880 to 1882 as a canon and the chancellor of the Anglican Diocese of the Free State under Bishop Webb.