Originally, Lonergan intended Insight to contain a substantial analysis of theological method, but circumstances in his life led him to postpone this application of his new ideas until he could write Method in Theology (1972). Nevertheless, themes relevant to Christianity exist through Insight, especially in the later chapters. In fact, he eventually reveals that the desire to know, which is at the heart of most of the book, is rooted in God and points to God.

Some readers have seen Insight as a philosophical search for faith. Lonergan does admit, in the epilogue, that he is a Roman Catholic believer and a professor of theology who believes in the harmony of faith and reason. He shares the traditional belief that reason can foster a fruitful understanding of the Christian mysteries, even though the human mind is incapable of plumbing the depths of God’s reality. For example, reason can help us to analyze the problem of evil, which exists because God respects human freedom. Lonergan understands sin as a failure of free will to choose a morally obligatory course of action. He believes that secular humanists are unable to deal insightfully with human evil, because to do so requires a transcendence of humanism and an acceptance of basic Christian values, especially self-sacrificial love.

These Christian values are the subjects of theology, and Insight is more a preparatory study to theology than a theological work itself. However, Lonergan believed that his cognitional theory had important implications not only for physical scientists but also for theologians and scripture scholars. Divine revelation, a treasure preserved and protected by the Church, is something that thinking people in every historical period have to come to terms with and from which they have gained profound insights.