Symbolism, Imagery, Allegory
Children are our future, the saying goes. If so, the future doesn't look too bright for the Church.
Most of the children we meet in the novel have no memories of a time before the persecution. The only priests they know are Padre José, the priest who renounced the faith and married in conformity with the new law, and the whisky priest, whose stench is as putrid as his sin.
Some of these children are more inclined to believe the government than they are to believe the stories their parents tell them. Luis, whose mother has been reading a book about a fearless young martyr, erupts in anger at the incredulity of the tale: "Nobody could be such a fool," he tells her furiously (1.4.33).
His imagination is lured by the sight of soldiers in the capital and the gun at the hip of the lieutenant. The sights, sounds, and smells of the church are entirely foreign to his mind.
Greene, however, has hope. It's Luis who arguably changes most in the novel—from a skeptical, angry boy to a responsible lad who helps hide a newly-arrived priest.