His mother, Mari Lewis, is a devout member of the Calvinistic Methodists and seeks to bring her two boys up in the same faith. Bob, the older brother, despite working as a miner, is keen on self-improvement. He teaches himself English and the books he reads lead him to doubt the simplicity of his mother's faith; he is excommunicated from the Calvinistic Methodists after attacking Rhys's schoolteacher when he caught the latter beating Rhys, but continues searching for the truth whilst becoming active as a leader among the miners in their fight against an incompetent English supervisor who is badly mismanaging the mine to the detriment of the owners and workers alike. After a workers' riot which he has tried hard to prevent, Bob is imprisoned on false charges; during his absence, the family declines into deep poverty. Meanwhile, the English steward is fired and replaced by his Welsh predecessor, who is also a deacon with the Congregationalists, and who sees that the family is provided for and that Bob is reinstated on good terms when he comes out of prison. Bob eventually comes to faith in a deathbed conversion following a mining accident, saying, after having been blinded in an explosion, "the light has come at last. Doctor, it is broad daylight!".