The protagonist of the story, the priest is waging a war on two fronts: haunted by his sinful past, he struggles internally with deep qualms about himself, and pursued by the authorities, he works to evade capture by the police for as long as he can. The priest is not a conventional hero: he is at times cowardly, self-interested, suspicious, and pleasure-oriented. That is to say he is human. The extraordinary hardships he has endured on the run from the government for eight years have transformed him into a much more resilient and mentally strong individual, although he still carries around with him strong feelings of guilt and worthlessness. He is self-critical almost to a fault.
What is remarkable about Greene's depiction of this person is that he refuses to spare us the priest's less-than-noble side, and yet also convincingly shows him overcoming his weaknesses and performing acts of great heroism. The most important single act comes near the end of the novel, when he decides to accompany the mestizo back across the border, to the state in which he is being hunted, in order to hear the confession of a dying man. The priest does not recognize the real value of his actions, nor does he fully comprehend what kind of impact he has had on people's lives. He tends to hear only from those people who have been hurt or disappointed by him in some way: Maria, Brigida, the pious woman. He does not see the many people whose lives have been touched merely by coming into contact with him or hearing about his death; Mr. Tench and the boy are the two most notable examples. Because this positive influence remains hidden to him, the priest does not have a true conception of the value of his life, and therefore, remains an extremely humble man to the day of his death. He also feels that he can never be truly penitent for his sexual relationship with Maria, since it produced Brigida, his daughter, whom he loves very deeply.