2 LBCF 2.3

This divine and infinite Being consists of three real persons,c the Father, the Word or Son, and the Holy Spirit.27  These three have the same substance, power, and eternity, each having the whole divine essence without this essence being divided.28  The Father is not derived from anyone, neither begotten nor proceeding. The Son is eternally begotten of the Father.29  The Holy Spirit proceeds from the Father and the Son.30  All three are infinite and without beginning and are therefore only one God, who is not to be divided in nature and being. Yet these three are distinguished by several distinctive characteristics and personal relations. This truth of the Trinity is the foundation of all of our fellowship with God and of our comforting dependence on him.

This divine and infinite Being consists of three real persons, the Father, the Word or Son, and the Holy Spirit.

Answers modalism, the persons just three modes

Matthew 28:19 ESV

19 Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit,

2 Corinthians 13:14 ESV

14 The grace of the Lord Jesus Christ and the love of God and the fellowship of the Holy Spirit be with you all.

These three have the same substance, power, and eternity, each having the whole divine essence without this essence being divided.

This answers Arianism

The creed at Nicea

(We believe) in one Lord Jesus Christ, the Son of God, begotten of the Father, only-begotten, that is, from the essence of the Father, God from God, light from light, true God from true God, begotten not created, of the same essence as the Father (homoousios: same essence)

Exodus 3:14 ESV

14 God said to Moses, “I am who I am.” And he said, “Say this to the people of Israel: ‘I am has sent me to you.’ ”

John 14:11 ESV

11 Believe me that I am in the Father and the Father is in me, or else believe on account of the works themselves.

1 Corinthians 8:6 ESV

6 yet for us there is one God, the Father, from whom are all things and for whom we exist, and one Lord, Jesus Christ, through whom are all things and through whom we exist.

The Father is not derived from anyone, neither begotten nor proceeding. The Son is eternally begotten of the Father.

John 1:14–18 ESV

14 And the Word became flesh and dwelt among us, and we have seen his glory, glory as of the only Son from the Father, full of grace and truth. 15 (John bore witness about him, and cried out, “This was he of whom I said, ‘He who comes after me ranks before me, because he was before me.’ ”) 16 For from his fullness we have all received, grace upon grace. 17 For the law was given through Moses; grace and truth came through Jesus Christ. 18 No one has ever seen God; the only God, who is at the Father’s side, he has made him known.

The Holy Spirit proceeds from the Father and the Son.

John 15:26 ESV

26 “But when the Helper comes, whom I will send to you from the Father, the Spirit of truth, who proceeds from the Father, he will bear witness about me.

Galatians 4:6 ESV

6 And because you are sons, God has sent the Spirit of his Son into our hearts, crying, “Abba! Father!”

All three are infinite and without beginning and are therefore only one God, who is not to be divided in nature and being. Yet these three are distinguished by several distinctive characteristics and personal relations. This truth of the Trinity is the foundation of all of our fellowship with God and of our comforting dependence on him.

Reasons to break fellowship universal

Trinitarian disagreements

Soteriology disagreements (Catholics)

Reaosons to break fellowship local

Baptism