Story of Two Monks

Can you identify a therapeutic key from this story told by William Bridges?

Once there were two monks who were traveling through the countryside during the rainy season. Rounding a bend in the path, they found a muddy stream blocking their way. Beside it stood a lovely woman dressed in flowing robes. "Here," said one of the monks to the woman, "let me carry you across the water." And he picked her up and carried her across. Setting her down on the farther bank, he went along in silence with his fellow monk to the abbey on the hill. Later in the evening, the other monk said suddenly, "I think you made an error, picking up that woman back on our journey today. You know we're not supposed to have anything to do with women and you held one close to you! You should not have done that!"  "How strange," remarked the other. "I carried her only across the water. You are carrying her still."