The Trinity

Thoughts on Westminster Confession of Faith, articles II.3, which you can find here.

God is one being, or divine essence.  And the Father, the Son and the Holy Spirit are each fully God.  The Father is not the Son, the Spirit is not the Father, and so on – they are different and distinguishable persons.  The Father is not begotten, the Son is begotten of the Father, and the Spirit is sent forth of the Father and Son.  The rational mind is not able to comprehend and fully harmonize these truths, but they are affirmed in Scripture.

The deity of Jesus the Son is shown in John 17:5, where He says He had glory with the Father before the world was.  He was/is/will be involved in the divine work of creation (John 1:3), providence (Col 1:17), sending the Spirit to us (John 16.7), and the last judgment (Jn 5:22).  Worship is due the Son – Heb 1:6; Rev 1:5-6.

The deity of the Holy Spirit is also clear in the Bible.  Lying to the Spirit is the same as lying to God, in Acts 5:3-4.  He has divine attributes: omnipresent (Psalm 139:7); omniscient (1 Cor 2.10-11).  The New Testament quotes the Old by saying, “The Spirit says,” a few times, showing that the Word of God was written or inspired by the Holy Spirit (Acts 28:25).