born of water

[Originalist]

16 Once when we were going to the place of prayer, we were met by a female slave who had a spirit by which she predicted the future. She earned a great deal of money for her owners by fortune-telling.

17 She followed Paul and the rest of us, shouting, “These men are servants of the Most High God, who are telling you the way to be saved.”

18 She kept this up for many days. Finally Paul became so annoyed that he turned around and said to the spirit, “In the name of Jesus Christ I command you to come out of her!” At that moment the spirit left her. (Acts 16:16-18)

Here Paul used the authority he possessed by virtue of the fact he was a Spirit filled child of God. It wasn't that anything supernatural had to be released by invoking the name of Jesus. When the demon realized by what authority Paul commanded him to leave, he knew he had no choice but to go. He knew that greater was he that was already IN Paul! Paul did not have to repeat the name of Jesus over and over like we think we have to.

Now certainly there is a necessity of using the name in order to demonstrate to unregenerate witnesses the authority that Jesus Christ possesses. This is why the Lord "confirmed the word with signs following".

I find the story of the sons of Sceva to be interesting, in particular the reaction this incident brought to the witnesses and others in that region that received word of it....

17 When this became known to the Jews and Greeks living in Ephesus, they were all seized with fear, and the name of the Lord Jesus was held in high honor.

18 Many of those who believed now came and openly confessed what they had done.

19 A number who had practiced sorcery brought their scrolls together and burned them publicly. When they calculated the value of the scrolls, the total came to fifty thousand drachmas.[c]

20 In this way the word of the Lord spread widely and grew in power.

This incident made them realize that it was not the name of Jesus itself that held power, but the one who bore that precious name, and that the apostles were endowed with authority by the one who bears that name (Jesus himself) because they were his followers!