An Example to Prove God Exists

Father Chris Alar, MIC, draws on the clear reasoning of St. Thomas Aquinas to explain why the universe cannot exist without a First Cause. Using the simple image of a train, he shows how every car moves because it is pulled by the one before it. Yet reason immediately asks the decisive question: what pulls the first car? Without an engine, the entire train stands still.

Saint Thomas teaches that reality works the same way. Everything that changes or comes into being is caused by something else. Created things do not explain themselves. If there were only an endless chain of causes with no beginning, nothing could exist at all. Because we do exist, reason leads us to affirm a First Cause who depends on nothing else. This uncaused cause is what we call God. As the “Catechism” affirms, “God can be known with certainty from created reality by the light of human reason” (“Catechism of the Catholic Church,” 31).

Sacred Scripture echoes this truth, reminding us that creation itself points beyond itself: “For from the greatness and the beauty of created things their original author, by analogy, is seen” (Wis 13:5; NABRE). Far from opposing faith, sound reasoning prepares the mind to trust God more deeply, helping us recognize that belief is not irrational, but grounded in truth discerned by reason.

The Church has always upheld this harmony between faith and reason, especially through the teaching of St. Thomas Aquinas, whose clarity continues to serve believers and seekers alike. Logical reflection does not replace faith; it strengthens it, guiding the intellect toward the God who is the source of all that exists.

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