In Fulton Sheen's Sermon about the "Parables of the Lost," he reflects on the significance of repetition in life and God's creation, using personal anecdotes and nature's cycles as examples. He delves into the meaning of the three parables from Luke 15 - the Lost Sheep, the Lost Coin, and the Prodigal Son - emphasizing God's immense concern for every individual soul and the joy in their redemption. Sheen also addresses the importance of acknowledging sin and the danger of its denial, highlighting the need for self-awareness and spiritual growth. The speech concludes with a call to deeper personal relationships with the divine and a critique of carelessness in spiritual guidance.