It is clear that the poor young boy who is the protagonist of this story and also its narrator is both looking forward to his first communion but also partly dreading it. He has been instructed to spend the night thinking of all of his many and manifold sins, as he has been told that if he forgets any sins and does not confess them he will not be able to receive First Communion. However, also, to help focus his mind on the eternal damnation that awaits him should he forget any of his sins, his mother has helpfully placed pictures of hell and various other phantasmagorical drawings:
Also, my mother had placed a picture of hell above the head of my bed and, because the room was covered in phantasmagorical pictures and because I wanted to save myself from all evil, I thought only of this picture.
This, in addition to the story that he then tells about the nun who instructs the children on the punishments they can expect to receive if they indulge in any "sins of the flesh," clearly highlights the kind of pressure that the protagonist faces. It is important to note the way that the author is clearly challenging the Catholic religion through its insistence on sin and punishment by exploring the impact that such a focus can have on a young and impressionable child.
The night before the boy's First Communion, the mother puts "phantasmagorical" pictures all around his bedroom. One of these is a depiction of hell. She wants to impress upon him the gravity of the sacrament he is about to receive by showing him all of the things sin can lead to or be caused by.