From the promises that are attached to baptism in the Bible, we know and believe that the Holy Spirit uses this sacrament to work faith in human hearts.
Baptism is not a free pass to heaven, many who have been baptized have rejected this gift.
Circumcision was a covenant between God and the nation of Israel in the OT.
Baptism follows faith as an act of obedience and an outward declaration of the already completely work of the Holy Spirit in the believers heart. It's an outward sign of the inward work that already happened, that is the baptism of the Holy Spirit which already occurred.
Water baptism does not activate or produce faith or the baptism of the Holy Spirit..