Casting down imaginations is the first major key for spiritual victory. The devil wants to use your imagination to birth and magnify fear. Mountains are best built within a corrupted imagination. God knows you can wander into the stormy sea of vain imaginations. He provided in His Word, however, ways to calm every storm. Scripture says the weapons of your warfare are not carnal but mighty through God to pull down corrupted thoughts that would rise against His Word, will and ways in your life.