During the period when Catholicism was outlawed in Mexico, the state of Tabasco enforces the ban rigorously, while many other states follow a don't-ask-don't-tell policy. But in Radical Socialist Tabasco, priests have been settled by the state with wives (breaking celibacy) and pensions in exchange for their renouncing the faith and being strictly banned from fulfilling pastoral functions. Those who refuse are on the run and liable to be shot.
A scene-setting introduction to some of the characters, who are enduring a barely satisfactory existence in the provincial capital, now gives way to the story of the novel's protagonist: a fugitive priest returned after years to the small country town that was formerly his parish. The narrative then follows him on his journey through the state, where he tries to minister to the marginalised people as best he can. In doing so, he is faced by many problems, not least of which is that Tabasco is also prohibitionist, with the unspoken prime objective to hinder celebration of the Sacrifice of the Mass, for which actual wine is an essential. Otherwise it is fairly easy to obtain beer or hard liquor, despite their being forbidden.
The unnamed "traitor to the state" is a 'whisky priest' who, among his other personal failings, had fathered a child in his parish some years before. Now he meets his daughter during a brief stay, but is unable to feel repentance. Rather, he feels a deep love for the evil-looking and awkward little girl and decides to do everything in his power to save her from damnation. His chief antagonist is the police lieutenant, who is morally irreproachable but unbending in outlook. While he is supposedly "living for the people", he puts into practice a plan of taking hostages from villages and shooting them if he discovers the priest has sojourned there without being denounced. On account of bad experiences with the church in his youth, there is a personal element in his pursuit.
For his part, the priest has remained on the run in order to serve the religious needs of the poverty-stricken agriculturists he meets, despite his deep sense of unworthiness. In order to save them from harm at the hands of the vengeful lieutenant, he now feels compelled to cross the mountainous border to the less stringent, neighbouring state. During this time, he twice encounters the lieutenant - once during a round-up in his village and then after he is imprisoned as a drunk – but is not recognised and allowed to go on his way. Near death after a perilous journey, he is rescued by the workers of the Lehrs, Protestant land-owners from the US, who nurse the priest back to health and help him make plans to reach the local capital.
As he sets out, the priest meets again a mestizo whom he has earlier learned to mistrust and who eventually reveals himself to be a Judas figure. The mestizo persuades the priest to return to hear the confession of a dying man just over the border, an American gunman who is the lieutenant's second target. Though suspecting that it is a trap, the priest feels compelled to fulfil his sacramental duty. Urged by the dying man to escape and save himself, the priest falls into the hands of the waiting lieutenant nevertheless. Though the lieutenant admits that he has nothing against the priest as a man, and rather admires him, the lieutenant persists that he must be shot "as a danger". On the eve of the execution, the lieutenant shows mercy and attempts to enlist the renegade Padre José to hear the condemned man's confession (which in extremis the Church would allow), but the effort is thwarted by Padre José's domineering wife.
The lieutenant is now convinced that he has "cleared the province of priests", but in the final chapter another covert priest arrives in the capital. A faithful Catholic woman, who has previously figured as reading pious tracts about the lives of native saints to her children, has added the protagonist to her repertoire of Christian martyrs and now agrees to harbour this new arrival.
