God the Holy Spirit, the third Person of the Most Blessed Trinity is often called God’s breath. Christ calls Him the “Paraclete” and “the Counselor” (Jn 14:16).
The Holy Spirit is not a dove, nor is He a “sense of spirituality.” He is “God’s Spirit, who reveals God, makes known to us Christ, his Word, his living Utterance, but the Spirit does not speak of himself. The Spirit who “has spoken through the prophets” makes us hear the Father’s Word, but we do not hear the Spirit himself. We know him only in the movement by which he reveals the Word to us and disposes us to welcome him in faith” (CCC 687).
We know the Holy Spirit, then, not by sight, but by effect. We see His effects in the world, through which He transmits the Father’s Word, the Only-Begotten Son of God. Now, this understanding of the Holy Spirit may seem like wishful thinking of His existence – a Spirit of God Who is somehow a Person, in fact fully God, just as much as the Father and the Son.
But just because we find it easier to conceive of God the Father and God the Son does not mean that God the Holy Spirit is not God. The Father reveals Himself blatantly throughout the Old Testament. Jesus Christ becomes incarnate in the New testament, not only revealing much about Himself, but also revealing much more about the Father. The Holy Spirit is mentioned less often in Scripture, and even when He is, it is often in indirect wording. However, there are still many scriptural instances where the Holy Spirit reveals Himself to be God.
When Ananias and Sapphira lie about withholding money from the early Church community, St. Peter accuses them: “why has Satan filled your heart to lie to the Holy Spirit and to keep back part of the proceeds of the land?… You have not lied to men but to God” (Acts 5:3-4). St. Peter clearly indicates that the Holy Spirit and God are One and the same Person.
“[A]s 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.’” (Heb 3:7-9). The author of Hebrews attributes the words of God (“put me to the test and saw my works”) to the Holy Spirit, claiming, therefore, that the Holy Spirit is God.
“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’” (Heb 10:15-17). Again, scripture demonstrates that the Holy Spirit words are those of the Lord God. Moreover, the Holy Spirit will put laws in hearts and write on minds, meaning that He must have an intellect and a will – an intellect to know the “laws” and a will to “write.” Mere powers or forms do not have an intellect or a will. Further, only God can forgive sins, for all sins principally offend God and only the offended can forgive the offender. Therefore, the Holy Spirit is God.
“When the Spirit of truth comes, he will guide you into all the truth” (Jn 16:13). No inanimate power can guide into truth, so the Holy Spirit must be animate. Moreover, only God can guide into all truth, for only God, Who is truth Itself, knows all truth.
Some also assert that the Holy Spirit cannot be God because the Bible uses neuter pronouns to refer to Him, not masculine ones. The Holy Spirit is referred to in certain places in scripture by the Greek, pneuma, which is a neuter word. But languages are assigned gender, not necessarily because they have to do or apply to their object in terms of masculinity or femininity. According to the Paideia Institute, an association specializing in ancient languages, “grammatical gender does not necessarily have anything to do with that noun’s biological sex! While nouns like puer (“boy”) and puella (“girl”) are respectively masculine and feminine, so are ager (“field”) and terra (“earth, ground”), neither of which have much to do with biological sex” (Grammar: Intro to Latin Nouns, Paideia Institute) . “God is spirit,” or “God is pneuma,” St. John says in his gospel (Jn 4:24). This does not mean that God is not a Person. He is. Thus, the Holy Spirit is God. Some groups, such as Jehovah’s Witnesses and Iglesia Ni Cristo, claim that the Holy Spirit is a force or power, but not a Person, and thus not God (The Holy Spirit is God, Catholic answers). We have seen why the Holy Spirit must be God because He guides into all truth and because He is animate, and because scripture blatantly says that He is God. Indeed, God does not have a gender as we do. But we refer to God by masculine pronouns because He has revealed Himself in this way. The Father has revealed Himself as “Father,” not “Mother.” The Son is not only the “Son,” not “Daughter,” but became a man, Jesus, when He became incarnate.