the Creator, the Almighty Most High God is certainly there in the Bible. in the beginning He made the heavens and the earth.
the Son, the Messiah, the Mediator between God and men is ceartainly there, Jesus of Nazareth.
the Holy Spirit is certainly there, the Spirit of Truth, given by Messiah to the hearts of believers, to guide, convict, and minister. elsewhere it is called the Spirit of God or the Spirit of Jesus. when we are baptized in the Spirit, we are made new, born again, saved, however one wants to express it. we are converted to Christan faith, and made new in and because of Jesus.
Jesus says that he and the Father are One, and that whoever has seen Him, as has seen God. the Spirit is the very Spirit of the One True God, and the Spirit of Jesus, too. so all three are there, and necesary for Christian life, and all three operate and move via he same will, mind, and holiness.
the only part where i would depart from traditional trinitarian belief is that i would not say that the Spirit is a "third person of a triune Godhead" but rather simply God's Spirit of holiness, truth, and righteousness, given to us through His Son by His grace in response to our faith. God wants us to follow Jesus, and we can not recieve His Spirit apart from Him.
i'm ok with trinitarians, and i'm ok with non-trinitarians. it doesn't bug me that the word "trinity" isn't in the Bile, or that most Christians understand the Holy Spirit to be a divine personage, a He. so long as Jesus is central, and followed, and adored and respected, that is cool. one needn't be a non-trinitarian or a trinitarian to be a follower of Jesus, and baptized with His Spirit.
in addittion, whatistruth, we are called to be witnesses for God's Son, the Messiah. we are called to share His name, His salvation, His love, and His Person with the peoples of the world. the people of Israel were called to be Yah's witnesses, witnesses and ambassadors of the One True God. yet believers in Messiah are called to be witnesses for Jesus Christ, and through Him, witnesses for God, too. for if we are Jesus' witnesses, we are God's witnesses, too (Matthew 10:40).
it is the Son of God who saves us and makes us new, through His reconciling death, grace, Living Person, and ability to bridge our humanity and God's holiness. in this age, God has chosen to make Himself known in and through Christ, and according to 1 John 2:23 no one who denies God's Son truly has God, either.
so Christ Jesus should be central in our lives. and because of Him, through Him, God becomes central to us, as we love God in, through, and because of the Lord.