The second thing is that the brothers overcame him "because of the word of their testimony." When our conscience is without offense, then our mouth can give testimony. When there is an accusation in our conscience, we can utter nothing. It seems that the more we speak, the lower our voice becomes. The meaning of testimony here is to testify to others, not to one's self. When you have the blood before God, you will have boldness before God, and you will have a testimony before man. Not only will you testify that sinners can be forgiven and man can be accepted because of Christ, but you will further testify of God's kingdom. "Testimony" means to tell others what there is in Christ, and the word of testimony is something which must be spoken forth. The overcomers must frequently proclaim the victory of Christ. Satan fears the most when this fact is repeated again and again. It is a fact that the kingdom of heaven will come; it is a fact that the Lord is King; it is a fact that Christ is victorious and forever victorious; it is a fact that Satan is defeated; it is a fact that the strong man has been bound and legally condemned; it is a fact that Christ has destroyed all the work of Satan on the cross. When we declare all of these facts, we have the testimony. When we proclaim that Christ is this and Christ is that, this is the testimony.
It is the word of testimony that gives Satan the greatest fear. Satan does not fear when we try to reason with him, but he does fear when we proclaim the facts. Satan does not fear when we talk theology or when we expound the Scriptures, but he does fear when we declare the spiritual facts. "Jesus is Lord" is a spiritual fact. Many people speak about Jesus as the Lord and explain how Jesus is the Lord, but Satan is not afraid in the least. However, when someone declares in faith that Jesus is Lord, Satan fears. He does not fear our preaching or theology, but the word of our testimony.
It is a spiritual fact that the name of Jesus is above every other name. We must declare it in faith, not only to men, but also to Satan. We often speak for Satan to hear; we purposely speak for him to hear. We call this the word of testimony. Even when we are alone in our room we can proclaim aloud, "Jesus is Lord." We can say, "The Lord Jesus is stronger than the strong man," or, "The Son of God has already bound Satan," etc. This is the word of our testimony.
Christians must rely upon prayer in everything, but sometimes the word of our testimony is more effective than prayer. In Mark 11:23 the Lord Jesus said, "Whoever says to this mountain, Be taken up and cast into the sea, and does not doubt in his heart, but believes that what he says happens, he will have it." The Lord Jesus did not say that what a person prays will come to pass, but that what a person says will come to pass. The Chinese have a proverb which says, "A composition can come immediately from one's mouth." But Christians can say, "An accomplishment can come immediately from one's mouth." God created the heavens and the earth by one word of His mouth. The incident in Mark 11 shows us that we can speak to the mountain. Only if we speak in faith will something be accomplished. Many times the power of prayer is not as strong as the power of proclamation. Many times we must use the word of testimony to deal with Satan.
When we read the book of Acts, we can see many words of testimony. In chapter three Peter and John saw the lame man at the gate of the temple, and what Peter did was to say to him, "Silver and gold I do not possess, but what I have, this I give to you: In the name of Jesus Christ the Nazarene rise up and walk." This is what is called the word of testimony. It is not beseeching God to deal with the situation, but dealing with it directly in the name of the Lord. In Acts 16, when Paul cast out the demon, he also used the word of proclamation: "I charge you in the name of Jesus Christ to come out of her." Immediately the demon came out.