What is the fine-grained topic of the following text: As smoke vanishes, let them vanish; and as wax melts from the presence of fire, so let the demons perish from the presence of those who love God and who sign themselves with the Sign of the Cross and say with gladness: Hail, most precious and life-giving Cross of the Lord, for Thou drivest away the demons by the power of our Lord Jesus Christ Who was crucified on thee, went down to hell and trampled on the power of the devil, and gave us thee, His honorable Cross, for driving away all enemies. Only return the topic.
The power of the Cross in Christianity