baptizing them in the name

of the Father and of the Son and of the Holy Spirit

Matthew 28:19

What does it mean to be baptized in the name of the Father and of the Son and of the Holy Spirit?

First, notice is the full Trinitarian formula presented here by Jesus in the Great Commission. One name - singular - one God, one essence, one nature. 3 persons - Father, Son, and Spirit. To be baptized in “this” name is to acknowledge the Triune God as distinguished from every other religion and every other god. Baptism in the name of the full Godhead is an act of separation, an act of distinguishing oneself entirely from the world.

Second, to be baptized in the name of the Father and of the Son and of the Holy Spirit is a recognition and a profession that you are a disciple, because of, and only because of, the grace of the Father to plan and initiate your salvation, the grace of the Son to die and secure your salvation, and the grace of the Spirit to apply Christ’s work to your life and thereby complete the Father’s plan. Your salvation is a cooperative work of extraordinary graces by every member of the Godhead - which means when you are saved, you are fully and forever saved! So to be baptized in the name of the Father and of the Son and of the Spirit is a profession that you are a disciple because of the Triune God.

Third, it also means you will remain a disciple, and live out your life as a disciple, and die as a disciple because of the Triune God. For God is now your heavenly Father and He is watching over you, you have been given to Christ by the Father and Christ is keeping you, and you have been sealed by the Spirit, so He will ensure that you make it!

Fourth, it also means every single point of being a disciple, from becoming a disciple to living as a disciple to persevering to the end as a disciple - every bit of glory goes to the Triune God - it is His work and He who began it will complete it.