The spirit of God is all pervasive and yet unseen character in the New Testament and the whole Bible. Ronald Brownrigg says in ‘Who’s Who the New Testament’ that “The Holy Spirit is thelife and activity of God at work in the world of nature and also in and through people” (p.257).

The Hebrew word ‘ruah’ used for spirit has actually no equivalent word in English and hence it is vicariously translated ‘breath’, ‘wind’ and spirit, life, etc. The equivalent Greek word in the New Testament is ‘pneuma’ which means ‘spirit’. The world spirit is used in the Bible both for good spirit and evil spirit. Here we are speaking only about the Holy Spirit, the Spirit of God.

The Catholic Church believes that the Holy Spiritis the third person of the Blessed Trinity or the Triune God. The Catholics believe that the Holy Spirit is a true God, equal to the other two Divine Persons, the Father and Son. The Catholic creed says that the Holy Spirit proceeds from the mutual love and will of the Father and the Son.In the New Testament the Holy Spirit is first mentioned in the Gospel according to Mathew.

Joseph was engaged to Mary. But before their marriage Joseph learnt that Mary was pregnant with child. So Joseph being a just man made plans to break the engagement privately. Then, anangel of the Lord in a dream said to him, “Joseph, descendant of David, do not be afraid to take Mary to be your wife. For it is by the Holy Spirit that she has conceived” (see Mt 1, 18-20).

The Holy Spirit appears again in the baptism of Jesus at River Jordan. John the Baptist says, “I baptize you with water to show that you have repented, but the one who will come after me will baptize you with the Holy Spirit and fire” (Mt 3, 11).Then, at the baptism of Jesus by John the Baptist,Mathew tells us that the Spirit of God came down like a dove and alighted on Jesus. The baptism and the Temptation of Jesus are narrated by all the three synoptic evangelists and the Holy Spirit is a significant character in all the narrations. Luke says, “Jesus returned from the Jordan full of the Holy Spirit and led by the Spirit into the desert where he was tempted” (Lk 4, 1-2).

After Jesus’ baptism and temptation, the first three evangelists speak of the Holy Spirit on the occasion of Jesus’ preaching in the synagogue of his home town Nazareth. Jesus reads from the book of the prophet Isaiah, “The Spirit of the Lord is upon me, because he has chosen me to bring good news to the poor” (Luke 4, 18).

Jesus speaking to his disciples about coming troubles and persecutions assures them that they need not worry about them. For, “When they bring you to trail, do not worry about what you are going to say or how you will say it; when the time comes, you will be given what you will say.

For the words you will speak will not be yours; they will come from the Spirit of your Father speaking through you” (Mt 10, 19-20).“And when you are arrested and taken to court, do not worry beforehand about what you are going to say; when time comes, say whatever is then given to you. For the words you speak will not be yours; they will come from the Holy Spirit” (Mk. 13, 11).

Later, when Pharisees accuse Jesus of driving out demons by their leader Beelzebul, Jesus defends himself saying “No, it is not Beelzebul, but God’s Spirit, who gives me the power to drive out demons, which proves that the Kingdom of God had already come upon you” (Mt. 12,28).

Once, teaching his disciples about prayer Jesus tells them to ask for the Holy Spirit “How much more, then, will the Father in heaven give the Holy Spirit to those who ask him!” (Luke 11, 13). In the fourth Gospel the Holy Spirit or the Spirit of God is also referred to as the Advocate, the Helper.

In the conversation with the Samaritan woman at Jacob’s well, Jesus tells her that people will worship the Father by the power of God’s Spirit; and that God is Spirit. “God is Spirit, and only by the power of his Spirit can people worship him as he really is” (Jn. 4, 24).

In the Gospel according to John during the long discourse after the Last Supper Jesus often refers to the Spirit of God with different functions especially as an Advocate, a Helper. The Spirit reveals Jesus and guides his disciples. Jesus promises that, “I will ask the Father, and he will give you another Helper, who will stay with you for ever. He is the Spirit who reveals the truth about God” (Jn. 14, 16-17).

Jesus says again, “I have told you this while I am still with you. The Helper, the Holy Spirit, whom the Father will send in my name, will teach you everything and make you remember all that I have told you” (Jn. 14, 25-26).
Jesus assures his disciples again that, “The Helper will come – the Spirit, who reveals the truth about God and who comes from the Father. I will send him to you from the Father, and he will speak about me” (Jn. 15, 26).

The Holy Spirit is Jesus’ gift to his disciples when he appeared to them after his resurrection.“Jesus said to them again, ‘Peace be with you. As the Father sent me, so I send you.’ Then he breathed on them and said, ‘Receive the Holy Spirit” (Jn. 20, 21-22).

In the first chapter of Acts just before his ascension Jesus tells his disciples that the Holy Spirit will come upon them with power, “But when the Holy Spirit comes upon you, you will be filled with power, and you will be witnesses for me in Jerusalem, in all Judaea and Samaria, and to the ends of the earth” (Acts 1, 8).

As promised by Jesus the Acts of the Apostles has described the coming of the Holy Spirit during the feast of Pentecost,the harvest festival of the Israelite-Jewish people.