In all, he wrote some thirty books encompassing a number of popular genres – public school stories, adventure yarns, fairy tales, novels and Christian allegories and fable.
Cule's most popular Christian works are The Man at the Gate of the World and Sir Knight of the Splendid Way, the latter recently reprinted by Lamplighter Publishing in the United States.
Cule began writing in his teens, and one of his first literary successes was an eisteddfod prize for a poem, awarded by the Welsh preacher poet Evan Gurnos Jones.
[3] Other poems published in the newspaper Barry Dock News included "The Duett Endeth",[4] "Verge of Night: A Fragment",[5]"Spring Visitors: A Ballad of Two Chestnuts"[6] and "Learning to Skate: In Seven Chapters".
[8] Cule gave this brief account of his early literary career: "I came to take to writing, I believe, because of my insatiable love of reading, and as a result, also, of my admiration for everybody who wrote books I liked.
In 1895 I was able to devote myself entirely to writing, and in 1899 Mr Melrose published two volumes, Sir Constant and Child Voices; while Messrs W. and R. Chambers brought out a little fairy book, Mabel's Prince Wonderful.
Melville published Cule's first two books in 1899 – Child Voices, a collection of sketches and stories about children, and Sir Constant Knight of the Great King, an allegory of the Christian life.
Chambers had earlier published a number of his adult short stories including "Lady Stalland's Diamonds", "The Anthropologist's Coat", "Old Mr. Jellicoe's Plan" and "Lord Cumberwell's Lesson".
Her death is also alluded to in a story from the fairy tale collection The Rose-Coloured Bus, which tells of a grieving woodcarver who makes a doll's house for his daughter.
In 1906 Cule was appointed on the recommendation of Andrew Melrose and Rev Carey Bonner to head the publishing activities of the Baptist Missionary Society (BMS).
Cule remained with the BMS for thirty years until his retirement, combining his professional editorial and publishing activities with his career as a popular writer.
Typical of these is Barfield's Blazer, described by one reviewer as "... a volume to be greatly prized and thoroughly enjoyed, the entire series of stories affording delicious reading accompanied by rare hearty schoolboy fun.
"[16] Rollinson and I, the story of a public school boy accused of an offence he did not commit and sent to Coventry, is a full-length novel that explores in greater depth the themes of personal integrity, moral courage and loyalty to friends.
[18][19] One reviewer commented: The wonderful adventures and encounters of "The Child Who Believes" are told in the most graphic and convincing manner, and the juvenile reader who remains incredulous of the existence of "The Old World" after reading the entrancing story of Mabel and her fairy prince, deserves to be passed over by Santa on his annual visit.
Neither story is an allegory but a careful reading of them reveals that for Cule (as with George Macdonald) the "storybook world" of the imagination is linked to the Christian concept of the Kingdom of Heaven.
Cule's novelette The Prince of Zell is a curiosity – a Ruritanian romance with a wildly improbable plot and a denouement that strains credulity to the limit.
He has a "chart of the journey," as the pilgrim has his roll, meets the peril of temptation in the "Palace of Sir Joyous," and finds it again in another shape in "The Black Knight of Law."
Drawing for its inspiration on Bunyan's Pilgrim's Progress, the Arthurian tradition of the questing knight and the New Testament epistles, it is a spiritually profound and richly detailed work, written in a language suggestive of another era with some of the finest examples of word painting Cule ever achieved.
Fullerton wrote of Cule's allegory: "For depth of experience and daintiness of touch, it may be placed alongside The Pilgrim's Progress itself without suffering by the comparison, and there can be no higher praise.
It tells of how Caspar subsequently forswears his wealth and privilege to stand at a city gate washing the feet of weary travellers, thus fulfilling Christ's mandate to his disciples.
He wondered whether to publish it after reading Henry Van Dyke's parable The Other Wise Man but decided his "Story of the Star" had its own spiritual truth that he was impelled to share.