The most difficult thing about the Christian concept of the Trinity is that there is no way to perfectly and completely understand it. The Trinity is a concept that is impossible for any human being to fully understand, let alone explain. God is infinitely greater than we are; therefore, we should not expect to be able to fully understand Him. The Bible teaches that the Father is God, that Jesus is God, and that the Holy Spirit is God.
1 Corinthians 8:6
6 yet for us there is but one God, the Father, from whom all things came and for whom we live; and there is but one Lord, Jesus Christ, through whom all things came and through whom we live.
2 Corinthians 3:17
17 Now the Lord is the Spirit, and where the Spirit of the Lord is, there is freedom.
2 Corinthians 13:14
14 May the grace of the Lord Jesus Christ, and the love of God, and the fellowship of the Holy Spirit be with you all.
9 For in Christ all the fullness of the Deity lives in bodily form,
6 For to us a child is born, to us a son is given, and the government will be on his shoulders. And he will be called Wonderful Counselor, Mighty God, Everlasting Father, Prince of Peace.
6 “This is what the LORD says— Israel’s King and Redeemer, the LORD Almighty: I am the first and I am the last; apart from me there is no God.
14 The Word became flesh and made his dwelling among us. We have seen his glory, the glory of the one and only Son, who came from the Father, full of grace and truth.
30 I and the Father are one.”
35 The angel answered, “The Holy Spirit will come on you, and the power of the Most High will overshadow you. So the holy one to be born will be called the Son of God.
23 “The virgin will conceive and give birth to a son, and they will call him Immanuel” (which means “God with us”).
19 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,
16 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. 17 And a voice from heaven said, “This is my Son, whom I love; with him I am well pleased.”
16 And I will ask the Father, and he will give you another advocate to help you and be with you forever— 17 the Spirit of truth. The world cannot accept him, because it neither sees him nor knows him. But you know him, for he lives with you and will be in you.
17 For the kingdom of God is not a matter of eating and drinking, but of righteousness, peace and joy in the Holy Spirit, 18 because anyone who serves Christ in this way is pleasing to God and receives human approval.