Catechism of the Catholic Church §2848 — excerpt
"Lead us not into temptation" implies a decision of the heart: "For where your treasure is, there will your heart be also.... No one can serve two masters."
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.