Thomas’ public career as a reciter, orator, poet and narrator began early. He began preaching when he was eighteen years of age, at the request of Siloa, Maerdy. He attended Pentre secondary school, Rhondda, before moving on to Gwynfryn school, Ammanford. He won a scholarship for local boys from Maerdy tenable at the University College, Cardiff. He was accepted by examination into the Memorial College, Brecon. He was ordained in June 1896 at Bethel Newydd, Mynyddislwyn, Mon. It was there, tracing the church's history, that he took to historical research. This was to become one of his main interests in life. In 1899 he moved to Buckley, Flints., as pastor of the English church, and whilst there he took advantage of the resources of St. Deiniol's Library, Hawarden. He played an active role in local government as a member of the county council and as chairman of Flintshire education committee. He was a member of the deputation which went before the Commission on the Disestablishment and Disendowment of the Church. In 1906 he moved and took charge of Markham Square church, Chelsea. There he co-operated with Lord Monkswell in promoting children's welfare. In 1912 he returned to Wales to take charge of the English church at Gnoll Road, Neath, where he stayed until his retirement in 1946. On his retirement he was made honorary minister of the church.

He won many prizes in the national eisteddfod. He was secretary of the literary committee of the national eisteddfod at Neath, 1918. He was a member of the Gorsedd of Bards and lectured widely on historical subjects. On the strength of his research and publications he was elected F.R.Hist.S. in 1919. He published a number of books and booklets: Y Lili fach wen a thelynegion eraill (1903); Breezes from the Welsh hills and other poems (1906); Notable Welshmen (1908); Ebenezer Jones, the neglected poet … (1909); Ystorïau difyr … (1908 and 1909); Mynachdai Cymru … (1910); Welsh painters, engravers, sculptors (1527-1911) (1912); Difyrrwch gwŷr Morgannwg … (1916); Hiwmor y Cymro … (1922); A history of the Quakers in Wales and their emigration to North America (1925); and Seth Joshua and Frank Joshua … (1926). He was the editor of The Official Guide to Neath from 1922 to 1941. He also published pamphlets in Welsh and English on the results of the Act of Uniformity, 1662, and short histories of Maes-yr-haf church, Neath, and Bethel Newydd church, Mynyddislwyn.

He m. Margaret Williams who predeceased him by four years. They had four sons and one daughter. The eldest son, Alyn, d. before his father. He was the first secretary of the Consultative Council on Technical Education in south Wales. Kenneth was a bank manager in Croydon, Penry was headmaster of Basaleg grammar school, and Bryn was minister of the Congregational church in Muswell Hill, London.

He d. 2 May 1953 and was buried in the new cemetery, Llanilltud Fach, Glam.