The reader of San Manuel Bueno, Martir which is translated as Saint Emmanuel the Good, Martyr is intrigued by a problem that plagues modern existence. Developments in science cause more and more people to question God's existence or at least question the facts about the creation of the earth and The Creation itself. People are often scared to question inconsistencies in the records relating to how the world began and the ensuing evolutionary process for fear of exposing truths they do not want to face. Miguel de Unamuno y Jugo poses these questions, in the form of Father Don Manuel, that so many want answers to, and the reader is guilt-free about exploring the questions and able to consider the priest's expressions in a detached way, maintaining an open mind. The priest is decidedly Christian in his philosophies of goodwill and temperance but does not extend his acceptance of Christian ideas to "la vida eterna" - eternal life.
Another modern concept is the mixing of religions and religious concepts as people are, in westernized cultures, allowed to consider and convert between religions, not lessening the importance of conversion but making an easier transition. There is less stigma attached to people's curiosity for other religions unlike previously (and even now in some cultures) when converts was ostracized or legally punished and when questioning your religion was taboo because of state imposed religious laws, whereas now there is often an admiration for a person who has the courage to question and convert. Even the priest's name - Manuel - is from Hebrew, and Emmanuel, meaning "God is with us," reveals the internal conflict that the priest faces as he challenges and revises his interpretation of the constants of his religion.
The cultures within which people and their religions exist are man-made and therefore, in some ways, may be seen as contrary to the basic tenets of religion as, instead of glorifying God, they seek to assert human concepts of what God wants and accepts, rather than looking to God for direction, another modern concept that illustrates the priest's detachment from the restrictive, unchanging Catholic environment in which he promotes an unchanging Christlike existence rather than promoting an existence that is not resistant to change, an existence that would be unlike the religion itself.