17 for the law was given through Moses; grace and truth came through Jesus Christ. (John 1:17 CSB)
The Mosaic Law, or the Law of Moses, is essentially covered in the first five books of the Hebrew Bible. This provided the basic parameters around which the Jewish community lived and how they lived out their faith.
Yet Christ brought grace and truth. No longer did how our approach to God require ritual cleansing or animal sacrifice.
However, many of the values in these original laws still provide useful structure. Even when it comes to how we approach God, it should be done in a revenant way, asking for cleansing of our sins and providing the sacrifice of our time and ourselves to truly speak to God.
While Christ provided a more open path to our interaction with God, our reverence for that interaction should remain holy.
When we take too casual an approach to God we are not giving Him the reverence due to a holy God. The Spirit is our continual companion, seeking to be that constant interaction. Chris is our savior to whom we owe everything. And God is our Father, due the respect of a father.
While true that the Holy Spirit, Chris and God the Father are three in one, each holds a special role in our lives; Spirit companion, Christ savior and God Father.