Let me firstly declare what all believers know to be true. We are in a battle here, but Jesus has been victorious over all that comes against us. We truly are victors and not victims. We overcome the enemy by the blood of the Lamb and the word of our testimony, Revelation 12:11.
We speak out of authority because we are under the authority of Jesus, and we are not overcome by the enemies slips, trips, and falls. In other words, the various traps that he has set in place have been sprung and rendered useless against us.
The enemy is rendered ineffective when we speak out of our authority, and we should always expect to see God move through that authority. Using the revelation that Holy Spirit gives us brings a deeper understanding of how we win these battles, remembering that the sword of the Spirit is God’s Word. God’s Word must be our weapon of choice, the rock on which we stand, and the food that sustains us. When the enemy comes in we put the Word of God, Jesus, between us and him.
2 Timothy 3:16 All Scripture is God-breathed (given by divine inspiration) and is profitable for instruction, for conviction (of sin), for correction (of error and restoration to obedience), for training in righteousness (learning to live in conformity to God’s will, both publicly and privately—behaving honorably with personal integrity and moral courage); so that the man of God may be complete and proficient, outfitted and thoroughly equipped for every good work.