In Short

1

God says he is one God.

“Hear, O Israel: The LORD our God, the LORD is one.”
Deuteronomy 6:4

“I am the first and I am the last;
apart from me there is no God.”
Isaiah 44:6

“Or is God the God of Jews only? Is he not the God of Gentiles too? Yes, of Gentiles too, since there is only one God.”
Romans 3:29-30

2

God calls the Father, the Son, and the Holy Spirit “God.”

“Praise be to the God and Father of our Lord Jesus Christ, the Father of compassion and the God of all comfort.”
2 Corinthians 1:3

“Theirs (the Jews’) are the patriarchs, and from them is traced the human ancestry of Christ, who is God over all, forever praised!  Amen.”
Romans 9:5

“My message and my preaching were not with wise and persuasive words, but with a demonstration of the Spirit’s power, so that your faith might not rest on human wisdom, but on God’s power.”
1 Corinthians 2:4-5

3

Christians refer to God as the Trinity, the three-in-one God.

“Go and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit.”
Matthew 28:19

“I pray that out of his glorious riches [the Father] may strengthen you with power through his Spirit in your inner being, so that Christ may dwell in your hearts through faith.”
Ephesians 3:16-17

“To God’s elect, strangers in the world, scattered throughout Pontus, Galatia, Cappadocia, Asia and Bithynia, who have been chosen according to the foreknowledge of God the Father, through the sanctifying work of the Spirit, for obedience to Jesus Christ and sprinkling by his blood: Grace and peace be yours in abundance.”
1 Peter 1:1-2