Though a letter, at 50,000 words long De Profundis becomes a sort of dramatic monologue which considers Douglas's supposed responses. Wilde's previous prose writing had assumed a flippant, chatty style, which he again employed in his comic plays. In prison Wilde was disconnected from his audiences, which Declan Kiberd suggested was possibly his harshest punishment. He characterises Wilde as an Irish critic of English social mores ultimately silenced for his polemics, and reports that while convalescing in the sick-bay, Wilde entertained his fellow-patients and carers with stories and wit until the authorities placed a warder beside his bed.
In a preface to the 1905 (and, later, 1912) edition, published as a popular edition by Methuen, Robert Ross, Wilde's literary executor, published an extract from Wilde's instructions to him which included the author's own summation of the work:
|“||I don't defend my conduct. I explain it. Also in my letter there are several passages which explain my mental development while in prison, and the inevitable evolution of my character and intellectual attitude towards life that has taken place, and I want you and others who stand by me and have affection for me to know exactly in what mood and manner I face the world. Of course, from one point of view, I know that on the day of my release I will merely be moving from one prison into another, and there are times when the whole world seems to be no larger than my cell, and as full of terror for me. Still at the beginning I believe that God made a world for each separate man, and within that world, which is within us, one should seek to live.||”|
According to Kiberd, Wilde follows Christ's individualist theme of self-perfection into a testing new zone: prison. Wilde, who had always looked to test English society's hypocrisies, declined the opportunity to flee to France. Kiberd places Wilde within the long tradition of prison writing by Irish Republican prisoners; when Wilde wanted to criticise the penal system after release, he contacted Michael Davitt, an Irish political reformer who had himself been imprisoned in England.