“And they overcame him because of the blood of the Lamb, and because of the word of their testimony.” Revelation 12:11
When you see the significance of the blood of Christ before God, you will have boldness before him and a testimony before man. Not only will you affirm confidently that sinners can be forgiven and accepted because of Christ, but you will further testify about God’s kingdom. “Testimony” means telling others what God has secured in Christ. It is a fact that Christ is King; it is a fact that he is victorious and will be so forever; it is a fact that he destroyed all the works of Satan on the cross; and it is a fact that the kingdom of heaven will come here upon this earth.
Satan does not fear when we try to reason with him, but he does fear when we proclaim these facts concerning Christ. He does not mind our knowledge of the Bible or our theology, but he has to yield when, out of hearts committed to Christ, we declare that Jesus Christ is Lord.