The third person of the Blessed Trinity, the Holy Spirit, is sometimes referred to as "the forgotten" member of the Godhead. He is, no doubt, the least spoken of among the three persons of God, the Father, the Son, and the Holy Spirit. Most students of our Catholic theology of the Trinity agree: Pneumatology, or the study of the Holy Spirit, is probably the least developed, after the study of the Son and the Father. It is, therefore, no surprise to find many Catholics ill-equipped to deal with some of the more notable errors concerning he who is "the Lord and giver of life." Thus, studying the person and nature of the Holy Spirit, though sometimes neglected, is crucial for us as Catholic apologists and as Catholics in general.
The most common attacks on Catholic belief concerning the Holy Spirit generally come from quasi-Christian sects such as the Iglesia Ni Cristo, Jehovah’s Witnesses, and others who deny the central mystery of the Christian faith—the Trinity. Both the personhood as well as the divinity of the Holy Spirit are rejected by these groups. The Holy Spirit is spoken of as a "force," or as "power" emanating from God, rather than as God himself. As Catholics, then, we must be able to respond to these two key misunderstandings concerning the Holy Spirit. The truths about the Holy Spirit are that 1. he is a person, and 2. he is God.
More than a Force
One of the first reasons given for denying the divine nature of the Holy Spirit is often to point out that the Greek word for "spirit" (pneuma) is neuter. John 14:26, for example, refers to the Spirit as to pneuma to hagion (the Holy Spirit). The claim goes that Father and the Son are clearly personal, masculine terms, and therefore, they are revealed as persons. "Spirit" being neuter, on the other hand, supposedly indicates we are dealing with an impersonal force rather than a person.
Catholics agree that spirit in Greek is a neuter term. But this does not necessarily mean the Holy Spirit is impersonal. Nouns in Greek are assigned gender as they are in many languages. In Latin and the modern romance languages, this is the case as well. For example, the Latin word for lance is lancea, which is feminine. This does not mean that lances or daggers are actually female and personal! The same can be said for Greek words such as kardia, heart. The fact that this Greek word is feminine does not indicate hearts to be female and personal. Nor does the fact that a word like baros, Greek for arrow, which is neuter, indicate arrows to be impersonal forces. Words are simply assigned gender in these languages.
Further, if being referred to as "spirit" indicates the third person of the Blessed Trinity is impersonal, then both angels and God the Father would have to be "forces" rather than persons as well. In John 4:24, Jesus says "God is spirit (Greek pneuma) and those who worship him must worship in spirit and truth." And in Hebrews 1:14, angels are referred to as "ministering spirits (Greek pneumata) sent forth to serve, for the sake of those who are to obtain salvation." The key here is to examine the context and usage of a word in Scripture, rather than just its "gender," in order to determine whether we are dealing with a person, a force, or perhaps just an arrow.
Speaking of the importance of context, the verse of Scripture used to "prove" the Holy Spirit to be an impersonal force actually demonstrates, when examined more fully, that the Holy Spirit is both personal and masculine. John 14:26 says: "But the Counselor, the Holy Spirit, whom the Father will send in my name, he will teach you all things, and bring to your remembrance all that I have said to you."
Three key points are in evidence here. First, "the Counselor" is ho paracleto in Greek, which is masculine, not neuter. Second, when the text says he will teach you all things the demonstrative pronoun (Gr. ekeinos) is used in the masculine singular. This is significant because the inspired author could have used the neuter ekeino, but he did not. If the Holy Spirit were an impersonal force, the inspired author would not refer to it as a he. And third, notice what the Holy Spirit does. Jesus says he will both teach and remind us "all that [he has] said to [us]." Action follows being. One cannot teach and remind if one does not have the intellectual powers unique to rational persons that enable one to do so. The Holy Spirit is clearly a person.
Indeed, the Holy Spirit is referred to in personal terms by our Lord throughout the New Testament. If we only consider John chapters 14, 15, and 16, the evidence is overwhelming. This is not to mention the abundance of examples we could cite throughout Scripture, both Old (in seed form) and New Testaments. Let’s take John 14:16-17 to start. Jesus says,
And I will pray the Father, and he will give you another Counselor, to be with you for ever, even the Spirit of truth, who the world cannot receive, because it neither sees him nor knows him; you know him, for he dwells with you, and will be in you.
In John 15:26-27, Jesus says,
But when the Counselor comes, whom I shall send to you from the Father, even the Spirit of truth, who proceeds from the Father, he will bear witness to me; and you also are witnesses, because you have been with me from the beginning.
And in John 16:7-15, Jesus makes it very plain,
Nevertheless I tell you the truth: it is to your advantage that I go away, 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; of sin, because they do not believe in me; of righteousness, because I go to the Father, and you will see me no more; of judgment, because the ruler of this world is judged. I have yet many things to say to you, but you cannot bear them now. When the Spirit of truth comes, he will guide you into all the truth; for he will not speak on his own authority, but whatever he hears he will speak, and he will declare to you the things that are to come. He will glorify me, for he will take what is mine and declare it to you. All that the Father has is mine; therefore I said that he will take what is mine and declare it to you.
The Holy Spirit is personal. He convinces of sin, teaches the truth, speaks, declares things that are to come, and so on. These texts leave no doubt as to the personhood of the Holy Spirit.
How to "Pour Out" a Person
One last obstacle for some who deny the personhood of the Holy Spirit is found in Acts 2:14-18. In this text, St. Peter describes the power of God being manifested on the day of Pentecost by quoting Joel 2:28:
But Peter, standing with the eleven, lifted up his voice and addressed them, "Men of Judea and all who dwell in Jerusalem, let this be known to you, and give ear to my words. For these men are not drunk, as you suppose, since it is only the third hour of the day; but this is what was spoken by the prophet Joel: ‘And in the last days it shall be, God declares, that I will pour out my Spirit upon all flesh, and your sons and your daughters shall prophesy, and your young men shall see visions, and your old men shall dream dreams; yea, and on my menservants and my maidservants in those days I will pour out my Spirit; and they shall prophesy.’"
The question is often asked, "How can you pour out a person? Is this not proof the Holy Spirit is a force rather than a person?" The answer is a resounding no! Consider Psalm 22. This is a messianic Psalm referring to our Lord’s Passion. But notice how it describes our Lord in verse 14: "I am poured out like water . . . " Would we say Jesus is just a force and not a person because he is "poured out" in this verse? Of course not! So it goes with the Holy Spirit. We do not deny the verses of Scripture indicating his personhood because he is described as being "poured out" in Acts 2:17.
The Holy Spirit is Omniscient
We should examine one key phrase from John 16 more fully when considering the truth that the Holy Spirit is revealed not only as a person, but as a divine person—God himself. Verse 13 tells us that the Holy Spirit "will guide [us] into all truth." We have a hint here of what we see even more plainly in texts like 1 Corinthians 2:11: Scripture indicates the Holy Spirit is omniscient, a quality that God alone possesses or can possess. "For what person knows a man’s thoughts except the spirit of the man which is in him? So also no one comprehends the thoughts of God except the Spirit of God." The reason St. Paul tells us "no one comprehends the thoughts of God except the Spirit of God" is because it would require infinite power to be able to comprehend the thoughts of God which are infinite. Romans 11:33-34 tells us: "O the depth of the riches and wisdom and knowledge of God! How unsearchable are his judgments and how inscrutable his ways! ‘For who has known the mind of the Lord, or who has been his counselor?’"
The fact that the Holy Spirit of God fully comprehends the thoughts of God proves beyond a reasonable doubt that his is, in fact, God.
The Lord and Giver of Life
Among the many texts revealing the Holy Spirit’s divinity, perhaps the most plain and unmistakable are found in Hebrews. First, we’ll examine Hebrews 3:7-10:
Therefore, as the Holy Spirit says, "Today, when you hear his voice, do not harden your hearts as in the rebellion, on the day of testing in the wilderness, where your fathers put me to the test and saw my works for forty years. Therefore I was provoked with that generation, and said, ‘They always go astray in their hearts; they have not known my ways.’"
Notice the Holy Spirit is synonymous with God himself. In Hebrews 10:15-17, the reference is even more clear:
And the Holy Spirit also bears witness to us; for after saying, "This is the covenant that I will make with them after those days, says the Lord: I will put my laws on their hearts, and write them on their minds," then he adds, "I will remember their sins and their misdeeds no more."
The Holy Spirit is revealed here to be both a person and divine. He is depicted as "bear[ing] witness," "establish[ing] a covenant," is referred to as "the Lord," "puts [his] laws on [our] hearts," and even forgives sins. How many Catholics realize when they recite the Nicene Creed every Sunday at Mass that they are clearly and concisely professing just what we see here in Scripture: The Holy Spirit truly is "the Lord and Giver of Life."