Lazarillo de Tormes traces the life of the down and out Lazarillo, commencing with his humble beginnings. It relates periods of time spent under various masters as he serves them and tries to survive in circumstances where he is treated unfairly and even abused. He is able, because of his cunning and lessons learned to serve his own purposes and so becomes an unlikely hero promoting the cause of the underdog and the poor man, but never willfully abusing others in his efforts to survive and better himself.
First, Lazarillo learns from a blind man who teaches him to be astute and to recognize the dishonesty in others. In what becomes a battle of wits, Lazarillo uses what he learns to actually escape from the blind man and next he serves a priest who would rather Lazaro almost starve than share his food with him. Even though there is food all around, Lazarillo must be content with nothing more than an onion every four days. Accordingly, Lazarillo steals from his master and is careful to disguise his theft so that the priest has no idea that it is him. However, he is ultimately discovered and dismissed. Avarice is, therefore, a weakness of the priest and this is hypocritical as, despite being a clergyman, he is surrounded by plenty; he is cruel and unyielding with no compassion such as a man of God should have. Avarice is one of the Deadly (Cardinal) Sins that the Church warns people against. Being guilty of avarice, or any of the deadly sins, ensures eternal damnation. The priest would warn others of this but lack the self-awareness to recognize his own sin.
The continuing thread of Lazarillo's attempts to survive but to never sacrifice his principles makes him a likable character. The dishonesty and hypocrisy of the priest furthers the author's purpose as the reader sees Lazarillo overcome his adversity. The reader becomes aware of the difference between Lazarillo's dishonesty and his master's hypocrisy. Even though Lazarillo is the one who must live by his wits, he is the one who rises above his circumstances whereas the priest simply survives at the expense of others, never because of his own efforts. Hence the reader can interpret the author's goal as a warning that there is no honor in taking advantage of those less fortunate and that being true to yourself is far more fulfilling and serves the greater good. "Inheriting noble estates" is no measure of a man's worth.