The Holy Spirit is one with the Father and Jesus Christ and serves as our comforter, guide, and advocate. Those who accept Jesus as their Savior receive the Holy Spirit to live inside them. The Spirit gives Christians guidance in living, an understanding of the Bible, and prayerfully intercedes for them.
As soon as Jesus was baptized, he went up out of the water. At that moment heaven was opened, and he saw the Spirit of God descending like a dove and alighting on him. And a voice from heaven said, “This is my Son, whom I love; with him I am well pleased.†~ Matthew 3:16
Then Jesus came to them and said, “All authority in heaven and on earth has been given to me. Therefore go and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, and teaching them to obey everything I have commanded you. And surely I am with you always, to the very end of the age.†~ Matthew 28:18-20
But the Advocate, the Holy Spirit, whom the Father will send in my name, will teach you all things and will remind you of everything I have said to you. ~ Luke 14:26
For through him we both have access to the Father by one Spirit... And in him you too are being built together to become a dwelling in which God lives by his Spirit. ~ Ephesians 2:18, 22