Power of the Blood
Christian believers are involved in a conflict. In this chapter, our enemy is called "the serpent," "the Devil," "Satan," and "the accuser of our brethren" (v. 9, 10). He began this conflict in the Garden of Eden and will continue until the Lord returns to reign.
The good news is that Satan, our enemy, is a defeated foe! Christ's atoning death and resurrection accomplished his complete and final defeat. The blood of Christ the Lamb causes God's people to prevail because it answers all of the enemy's accusations. Satan controls and defeats humankind through guilt and accusations. He is a blackmailer. However, the saints know that the blood has satisfied all of the charges against them, joined them to God, and provided them with every necessary provision to defeat Satan!
God has declared us righteous and victorious, and in the Apostle John's revelation of the final conflict, the message came through: :They overcame [Satan] by the blood of the Lamb. Our power to overcome is the same!