He saved us, not because of righteous things we had done, but because of his mercy. He saved us through the washing of rebirth and renewal by the Holy Spirit, whom he poured out on us generously through Jesus Christ our Savior, so that, having been justified by his grace, we might become heirs having the hope of eternal life.
Titus 3:5-7 NIV
The Trinity is a core belief of orthodox Christianity. This doctrine is taught in the Scripture but not clearly articulated there and is challenging to understand. It took many years, and much discussion before a formal definition of the Trinity could be derived from what Scripture has to say about the working of God. We believe that there is only one God. And that he is revealed to us in three persons, the Father, the Son, and the Holy Spirit. The three are of one essence yet are individual persons. And the title of Trinity reflects that. Tri-unity, three persons, united together in one being.
The Work of the Trinity
This is one of a handful of passages that show the working of the triune God, the Trinity. God the Father orchestrated our salvation. The washing of rebirth and renewal comes through the Holy Spirit. And the Father pours out the Holy Spirit on us through the Son, Jesus Christ, our savior. The Father works through the Son to save us. And the Father gives us the Spirit to give us new life and to enable that life.
There is much more to the triune God we worship and serve than is expressed here. But this passage helps us see how all the persons of the triune God work in our salvation. God is beyond our comprehension. But he is worthy of our praise and adoration.