As a preacher, he was undoubtedly the most popular and powerful of the age in Wales. He had the most profound convictions of the truths of the gospel, a thorough acquaintance with the Scriptures (without a shade of doubt as to their literal infallibility), and withal a logical mind to use them to the purpose of his preaching. He had a virile imagination, exceptional gifts of oratory, a strong face, and a powerful voice. In preaching he taxed all the resources of his mind and body, making effective use of his arms and especially his forefinger, and because of his vehemence, ardour, and deep seriousness he had a wonderful effect on his hearers. Because of his popularity as a preacher and his great oratorical powers, he became a foremost leader in the connexion, and since he was a man of strong will, an inflexible mind, and imperious nature, he could not be easily opposed. He entertained ultra-Calvinist views on Election and the Atonement. For a time he preached what was called a ‘limited’ Atonement, i.e. that the merits of the death of Christ exactly balanced the sins of the Elect, and of them alone; and he opposed men like Thomas Jones (1756-1820) (q.v.) of Denbigh and John Jones (1796-1857) (q.v.) of Tal-y-sarn, whose views were more liberal.

He played a prominent part in the drawing up of the Confession of Faith (1823) and the constitutional deed (1826) which incorporated all property (such as chapels) as the property of the connexion as a whole; and it was on his advocacy that this property-right was tied up with belief in the strict letter of the Confession. As a politician he was conservative in his views and he opposed every movement towards freedom of thought and action, e.g. the Catholic Emancipation Act and the Reform Bill of 1832. He called the supporters of these measures ‘rebels,’ while some of his opponents dubbed him ‘the Pope of Anglesey.’ To the end of his life he looked upon the idea ‘vox populi, vox Dei’ as a proof of infidelity. As a social reformer his zeal for temperance and purity of morals brought his powerful preaching to bear on many customs of the times and was thereby the means of putting down many corrupt and degrading practices such as wakes, hiring-fairs on Sundays, etc. He was a keen supporter of the Bible Society and travelled far and wide to establish branches of it, and also of the London Missionary Society. In spite of his conservatism, we find him in his later years advocating better education for the ministry, and he encouraged Lewis Edwards to open a school at Bala (1837) to this end. [His published works are listed in the Cardiff Welsh Library Catalogue.]