Equally important to the understanding of the Trinity is the belief that the Holy Spirit is God. The third person of the Trinity is fully and equally God.
The Jehovah Witnesses will argue that the Holy Spirit is not a person, but rather God’s power in action, a “force.” For example, in Luke 1:35 the angel tells Mary that “The Holy Spirit will come upon you, and the power of the Most High will overshadow you.” And passages like Psalm 8:3 where creation is called the work of God’s “fingers,” or Psalm 19:1 where it is referred to as God’s “handiwork” are seen as evidence that the Holy Spirit is simply God’s active power, not a unique person.
And while the Bible will capitalize Holy Spirit and refer to him as “he,” the New World Translation published by the Watchtower Society does not use capital letters and most often refers to the Holy Spirit as “it.” This diminishes His personhood and directs the reader to a different conclusion.
One passage that is not altered in this way in the NWT is John 16:7-8 where Jesus tells the apostles that “for if I do not go away, the Counselor will not come to you; but if I go, I will send him to you. And when he comes, he will convince the world of sin and of righteousness and of judgment.” There is however a footnote that Jesus used the term “helper” as a personification of the holy spirit, an impersonal force.
Assuming we have a valid translation, throughout Scripture we see that the Holy Spirit speaks, teaches and acts and is a person – Luke 12:12, John 14:26, John 14:16-17, John 16:13, Acts 8:29, Acts 13:2, Acts 28:25, Romans 8:26-27, 1 Corinthians 2:11, 1 Corinthians 12:11, and Ephesians 4:30 are all examples of this.
And St. Paul invokes the Holy Trinity in 2 Corinthians 13:14 when he says “The grace of the Lord Jesus Christ and the love of God and the fellowship of the Holy Spirit be with you all.” That invocation should be very familiar to Catholics as we begin each Mass with the same prayer offered to us by the priest.
In Acts chapter 5, we read of Ananias and Sapphira, who sold property but chose to only give part of the proceeds to the Church and lied in the process. Peter asked Ananias “why has Satan filled your heart to lie to the Holy Spirit and to keep back part of the proceeds of the land?” He then tells him that “You have not lied to men but to God” (Acts 5:1-5). We can see in Scripture that the Holy Spirit is both a unique person and is God.
While Scripture does not use the word “Trinity” or explicitly express the dogma, the seeds of this dogma can indeed be found within its pages.