Throughout his life, Griffith was a storm-centre. His support (in the press) of the report of the Commission on Education in Wales ( 1847 ) exposed him to bitter attack from the Nonconformists , particularly at Aberdare . On the other hand, towards the end of 1848 he drew upon himself the hostility of ecclesiastical authorities, by criticizing his church's indifference towards the Welsh -speaking population, as shown by the appointment of monoglot Englishmen to Welsh benefices. The dean and chapter of Gloucester , again, were attacked by him for taking revenues from Aberdare parish without due return — his action led the chapter to contribute towards a curacy there. Later on, especially in 1868 , he spoke and wrote vigorously against ritualism. When the disestablishment controversy flared up, in July 1883 , he wrote: ‘I have been for years convinced that nothing but Disestablishment, the separation of the Church from the State, can ever reform the Church in Wales.’

With all this, Griffith was an energetic parish minister . He held the first Anglican services at Hirwaun , got a church built at Trecynon , a church school at Cwm-bach , a new church ( S. Elvan ) and a vicarage at Aberdare . In the town, he tried to establish a mechanics’ institute , a reading room and lending-library ( 1849 ), and public lectures of which he gave the first. He won esteem by his practical aid after colliery disasters and his efforts to obtain financial aid for widows and orphans; and his pulpit eloquence drew admiration. At Merthyr Tydfil , again, he made himself conspicuous in the social and philanthropic life of the town.

[He has sometimes been confused with John Griffiths ( 1820 - 1897 ) (q.v.) .]