According to the Westminster Shorter catechism, baptism and the Lord’s supper are efficacious for salvation:
Q. 91. How do the sacraments become effectual means of salvation?
A. The sacraments become effectual means of salvation, not from any virtue in them, or in him that doth administer them; but only by the blessing of Christ, and the working of his Spirit in them that by faith receive them.
Thus, when we remember our baptism, we are supposed to trust that Christ’s blessing attended it and that the Spirit worked in it. Among other things this means we should
- Give thanks to God for “the privileges and benefits conferred” by baptism,
- Be humbled by “our sinful defilement, our falling short of, and walking contrary to, the grace of baptism“
- Grow up “to assurance of pardon of sin“
- Grow up to assurance “of all other blessings sealed to us in” the sacrament of baptism.
- Draw strength “from the death and resurrection of Christ, into whom we are baptized, for the mortifying of sin, and quickening of grace“
- Endeavor “to live by faith“
- Exhibit behavior “in holiness and righteousness, as those that have therein given up their names to Christ” in baptism
- Walk “in brotherly love, as being baptized by the same Spirit into one body“
And when we receive the Lord’s Supper, we should trust that by the working of the Holy Spirit we truly (though not by any transmission of physical particles) partake of Christ’s humanity so that our union with him and with other Christians is strengthened, for our “spiritual nourishment and growth in Him.”
Presbyterians would seem a lot more familiar and acceptable to American fundamentalists and many Evangelicals if they would not teach and preach these things. In fact, they would also seem a lot more rational to many Americans in general if they stripped the Faith down to simply some core affirmations one must profess and a list of behaviors–without including all this stuff about how rituals are effective for salvation. But they would be doing violence to Scripture and even weakening the Gospel.
But how many Presbyterian ministers preach and conduct the affairs of the church in such a manner as to indicate a functioning concurrence with what Westminster teaches? Some do but a good many who vehemently affirm Westminster deny it in their conduct all too often.