Here is a classic statement of the reformed view of the Sacraments, even if current reformed people do not know it. Let me make a couple of points about what Calvin says.
1. All efficacy in the sign is to be assigned to the Spirit, but this does not mean we substitute Spirit baptism for water baptism. The Spirit works through the sign. The Spirit doesn’t work outside of the sign. Thus we cannot disconnect baptism with water and baptism by the Spirit.
2. Baptism is always efficacious for the believer. Here is quote from the Westminster Shorter Catechism saying the same thing as Calvin:
“Q88: What are the outward means whereby Christ communicateth to us the benefits of redemption?
A88: The outward and ordinary means whereby Christ communicates to us the benefits of redemption, are his ordinances, especially the Word, sacraments, and prayer; all which are made effectual to the elect for salvation.”
3. Baptism, like the preaching of the Gospel, is an offer of the grace of God.
4. Baptism, like the preaching of the Gospel, can be rejected by the hardness of men’s hearts.
5. The proof that someone has accepted their baptism is newness of life.