spiritual warfare: the sword of the SPIRIT
As we all know, times are getting darker and darker. The evil ones have been released in a even greater measure like no time before. The very portal holes to the demonic realm are oozing through into our dimension through technology like CERN.
As believers in JESUS CHRIST we must arm ourselves in the spirit realm and be offensive, as well as defensive, to the spiritual attacks of the enemy. I have been learning, through necessity, how to use our spiritual armor, especially, the 'sword,' which is the WORD of GOD.
How is the WORD of GOD like a sword? With it we can cut down and cancel the very assignments of satan that comes against us. When we STAND on the WORD of GOD and declare it out loud, then the demons MUST OBEY! When satan tempted JESUS, how did JESUS respond? With the WORD of GOD and the devil left! 
This is the pattern that we need to follow! When attacked, we must know the WORD well enough, so we can find that corresponding verse that we can wield in the SPIRIT.
One way to do this, is to start a notebook of verses under different topics. I started a 'little black notebook' years ago, that is divided under many categories, like, health, provision, fear, anxiety, stress, temptation, etc. Then, when I am attacked, I go right to those verses and claim them OUT LOUD and command the demon(s) who is attacking to flee in the name of JESUS.
However, there is one thing to note: whenever you are engaging in spiritual warfare, you must be completely yielded to GOD and all sins confessed. As it says in James 4:7, if you are SUBMITTED to the LORD, and RESIST the devil.....he must flee!!!
As the body of CHRIST, we need to learn how to fight in the SPIRIT! If we don't, then the enemy will come in like a flood and try to get the upper hand in our life. So, next time, you find yourself in a situation that brings darkness instead of light, go to the WORD of GOD, find a related verse that applies, declare it OUT LOUD, and tell the enemy he must flee according to the WORD OF GOD!
"For our struggle is not against flesh and blood, but against the rulers, against the authorities, against the powers of this dark world and against the spiritual forces of evil in the heavenly realms." Ephesians 6:12
"Therefore put on the full armor of God, so that when the day of evil comes, you may be able to stand your ground, and after you have done everything, to stand." Ephesians 6:13
"Submit yourselves therefore to God. Resist the devil, and he will flee from you." James 4:7
"For the word of God is alive and active. Sharper than any double-edged sword, it penetrates even to dividing soul and spirit, joints and marrow; it judges the thoughts and attitudes of the heart." Hebrews 4:12
 "Then Jesus was led by the Spirit into the wilderness to be tempted by the devil. After fasting forty days and forty nights, he was hungry. The tempter came to him and said, “If you are the Son of God, tell these stones to become bread.”
Jesus answered, “It is written: ‘Man shall not live on bread alone, but on every word that comes from the mouth of God.’
Then the devil took him to the holy city and had him stand on the highest point of the temple. “If you are the Son of God,” he said, “throw yourself down. For it is written:
“ ‘He will command his angels concerning you,
and they will lift you up in their hands,
so that you will not strike your foot against a stone.”
Jesus answered him, “It is also written: ‘Do not put the Lord your God to the test.’ Again, the devil took him to a very high mountain and showed him all the kingdoms of the world and their splendor. “All this I will give you,” he said, “if you will bow down and worship me.”
Jesus said to him, “Away from me, Satan! For it is written: ‘Worship the Lord your God, and serve him only.’
Then the devil left him, and angels came and attended him." Matthew 4:1-11