Why the Sword?

The sword of the Spirit is the Word of God. It’s not called the sword of Jesus nor the sword of the Father but of the Holy Spirit. That means that the Word of God is empowered by the Holy Spirit. The power of the Spirit is released by God’s Word. 

Victory over the enemy is possible by using the sword. Jesus modeled that for us in the wilderness. Jesus didn’t use His own name or divine nature to cause the devil to be defeated. He used the Scriptures.  He used the sword of God’s Word. And this sword works every time.

It’s important to emphasize that Jesus spoke the Scriptures out loud against the devil. “But He answered and said, ‘It is written’” (Matthew 4:4). Most of the devil’s attacks will be in our mind, but our fight against these attacks must be with our mouth. When Satan fights you in the form of your thoughts or feelings, don’t fight back with “thoughts.” Open your mouth and speak out the Scriptures as Jesus did. The Word of God declared out of your mouth has the same power as the Word of God out of Jesus’ mouth. Fighting demonic thoughts with human thoughts doesn't bring victory. Demonic attacks are fought with the sword which is God’s Word spoken out of your mouth. 

Source: (Vladimir Savchuk)