Alan D. Strange
Baptism testifies to us of God's gracious, saving work (Matt. 28:19). He uses means to communicate his saving grace to his people by his Spirit (Acts 2:37-47). Christ's mediatorial work (Westminster Confession of Faith, chap. 8) is applied to us, then, by his Spirit through appointed means, namely, the Word, the sacraments, and prayer (Westminster Shorter Catechism, Q. 88; WCF 25.3). Baptism, as a sacrament, is one of those means.
That God gives us his salvation through means indicates that he is no distant, absentee landlord, but a God who delights to dwell with his people and to draw near to them as they draw near to him (and each other, WCF 26.1) in the means of grace. A right understanding of the Spirit's ministry to us through the means of grace serves as an antidote to the practical deism that can afflict us even in the Reformed faith.
The Westminster Larger Catechism instructs us as to the basic nature of baptism:
Baptism is a sacrament of the new testament, wherein Christ hath ordained the washing with water in the name of the Father, and of the Son, and of the Holy Ghost, to be a sign and seal of ingrafting into himself, of remission of sins by his blood, and regeneration by his Spirit; of adoption, and resurrection unto everlasting life; and whereby the parties baptized are solemnly admitted into the visible church, and enter into an open and professed engagement to be wholly and only the Lord's. (Q. 165; cf. Gal. 3:26-27; Titus 3:5; Rom. 6:3-5) 
This answer, first of all, tells us that baptism is a sacrament of the new covenant. WLC 164 previously states that there are two sacraments, baptism and the Lord's Supper. WLC 162 describes a sacrament as a "holy ordinance instituted by Christ in his church, to signify, seal, and exhibit unto those that are within the covenant of grace, the benefits of his mediation; to strengthen and increase their faith, and all other graces; to oblige them to obedience; to testify and cherish their love and communion one with another; and to distinguish them from those that are without." So baptism, as a sacrament, is a sign, seal, and exhibition—or application, as J. G. Vos (citing A. A. Hodge) explains—to those that are within the covenant of grace of the benefits of the mediation of Christ.
Such a sign and seal is to be given only to those who are in the visible church. WLC 166 teaches that "baptism is not to be administered to any that are out of the visible church, and so strangers from the covenant of promise, till they profess their faith in Christ, and obedience to him." Profession of faith brings one who has not previously been baptized into the visible church, at which point baptism is administered. WLC 166 continues: "But infants descending from parents, either both, or but one of them, professing faith in Christ, and obedience to him, are in that respect within the covenant, and to be baptized." Thus, baptism, as sign and seal, is performed on those who are within the covenant, either by profession of faith or by being born within the covenant (i.e., by having at least one parent who professes faith).
Theologians often distinguish between the internal and the external aspects of the covenant of grace, noting that all who are within the visible church enjoy, at least, the external aspects of that covenant (cf. WLC 63). WLC 31 teaches that "the covenant of grace was made with Christ as the second Adam, and in him with all the elect as his seed." Thus, only the elect are in the covenant, both internally and externally. But, as we see from WLC 166, infants of even one professing parent are "in that respect" within the covenant and thus to be baptized, to enjoy this mark of the visible church. Note that such infants are not baptized and brought into the covenant. Rather, they are, by virtue of their birth, already in the covenant, and rightfully heirs of all the privileges that pertain to those in the visible church. Baptism is one of those privileges, serving as "a sign and seal of our regeneration and ingrafting into Christ, and that even to infants" (WLC 177).
Baptism, as a sacrament, is purposed to strengthen and increase faith, whether of the adult or the infant. "The grace of faith," WCF 14.1 teaches, "whereby the elect are enabled to believe to the saving of their souls, is the work of the Spirit of Christ in their hearts, and is ordinarily wrought by the ministry of the Word, by which also, and by the administration of the sacraments, and prayer, it is increased and strengthened." Note that, although baptism is a sign and seal of our regeneration and ingrafting into Christ, the Spirit's gift of faith that makes efficacious the means of grace is ordinarily wrought by the ministry of the Word, especially preaching (cf. WLC 155). Baptism is said to be, together with the Supper, a means of increasing and strengthening the faith that is "ordinarily wrought by the ministry of the Word."
That faith comes primarily and usually, first of all, through hearing does not mean, of course, that baptism is unimportant, any more than an affirmation of the primacy of preaching means that the Supper in insignificant. It is the case that "grace and salvation are not so inseparably annexed unto [baptism], as that no person can be regenerated, or saved, without it; or, that all that are baptized are undoubtedly regenerated" (WCF 28.5). Even so, however, it is also true that it is "a great sin to contemn or neglect this ordinance" (WCF 28.5). Baptism is a gracious gift of God to his covenant people and is not to be neglected.
Is baptism efficacious or not? Indeed it is:
The efficacy of baptism is not tied to that moment of time wherein it is administered; yet, notwithstanding, by the right use of this ordinance, the grace promised is not only offered, but really exhibited, and conferred, by the Holy Ghost, to such (whether of age or infants) as that grace belongeth unto, according to the counsel of God's own will, in his appointed time. (WCF 28.6)
Baptism is no bare sign or empty seal, but really confers (gives) and exhibits (applies) grace to God's own by the Holy Spirit, in God's appointed time. It is true that only the elect truly receive God's saving grace. Those in the visible church who are not elect do not receive the grace of faith that saves souls. But the fact that the means are efficacious only for the elect does not call into question the validity of any particular baptism.
Even as the purpose of meditating upon God's predestination is to provide comfort for souls that know that they have no hope without the electing love and mercies of a covenant God (WCF 3.8), so baptism ought to be an incitement to believe God's promises. For anyone to speculate that they themselves or any other particular persons might be reprobate is utterly without foundation in the Word of God. Similarly, all those baptized in the name of the blessed, holy, undivided Trinity in water by one duly authorized to baptize should embrace in faith the promises that were signified and sealed to them in their baptism. All the baptized have a warrant for faith and should not question whether they do because they are uncertain of their election. We may be confident that the means that God has appointed are efficacious.
Baptism is a means that God uses to bestow his saving favor on us, to strengthen and increase our faith, to speak in baby talk to weak and needy people like us. Just as the Word itself, and its preaching in particular, is accommodated to us as sinful creatures, as Calvin observed, so also does baptism, signifying the washing away of our sin by the blood of our Savior and sealing to us all the blessings of salvation, speak to us on our level of understanding. That baptism is meant to build us up in our faith is seen particularly in WLC 167.
WLC 167 poses the question, "How is our baptism to be improved by us?" This is an older way of asking how it is that we might, as baptized, make the most of our baptism. The answer is instructive for us:
The needful but much neglected duty of improving our baptism, is to be performed by us all our life long, especially in the time of temptation, and when we are present at the administration of it to others; by serious and thankful consideration of the nature of it, and of the ends for which Christ instituted it, the privileges and benefits conferred and sealed thereby, and our solemn vow made therein; by being humbled for our sinful defilement, our falling short of, and walking contrary to, the grace of baptism, and our engagements; by growing up to assurance of pardon of sin, and of all other blessings sealed to us in that sacrament; by drawing strength from the death and resurrection of Christ, into whom we are baptized, for the mortifying of sin, and quickening of grace; and by endeavoring to live by faith, to have our conversation in holiness and righteousness, as those that have therein given up their names to Christ; and to walk in brotherly love, as being baptized by the same Spirit into one body.
This answer suggests that "improving our baptism" is frequently neglected to our detriment. We ought to make much of our baptism, especially in the time of temptation and when we are present at the baptism of others. Luther, when tempted, would often reply, "I am a baptized man." This was his vivid way of resisting the devil and reminding himself that, because he was declared God's freedman, his freedom was to be used, not in servitude to sin, but in joyful service to Christ. Temptation always involves the enticement to idolize the creature, perverting God's good gifts from their proper usage, enlisting the creature to provide what only the Creator can provide. As we remember that we are Christ's, signed and sealed as his, we are strengthened to die to sin and live to righteousness.
We ought, then, seriously and thankfully to consider the nature of our baptism. Christ instituted it to apply the blood that cleanses us from all sin, both to justify and to sanctify us. Our baptism speaks to us of that unqualified acceptance that we have with our God by his declaration of righteousness that we enjoy in justification, and that perfectly in this life. It also speaks to us of the transformative work that goes on in sanctification, a work neither equal in all, nor in this life perfect in any, but growing up to perfection (WLC 77). Considering all the ways that WLC 167 speaks about improving our baptism, Vos writes that "these various experiences and duties, taken together, mean a continuous, serious undertaking to live a faithful, consistent Christian life, according to the teachings of the Word of God, all along the line. As baptism stands for salvation from sin, improving our baptism involves taking salvation from sin seriously, in actual living experience."
In recent years, there has been a growing sense of the place and the efficacy of the means of grace, including the sacraments. In the OPC and other Reformed and Presbyterian churches, at least in some measure, there has been a revived commitment to "the outward and ordinary means whereby Christ communicates to his church the benefits of his mediation" (WLC 154). While we acknowledge that only the sovereign Spirit can empower these means, either in ordinary or extraordinary ways (as we see at different points throughout church history), it is surely our duty diligently to attend upon them and wait upon our gracious God for his blessing.
Church members are starting to realize that the faithful preaching of the Word of God is not simply "sharing," but the effectual application of God's Word to the hearts and lives of hearers (1 Thess. 2:13; WLC 160). Similarly, baptism and the Lord's Supper are being appreciated as more than bare memorials. The real presence is being more appreciated in the latter, and the former is being better understood as a sign and seal of our saving union with Christ (Gal. 3:27; Rom. 6:3; WLC 165). Furthermore, a renewed sense of our inability and of God's great grace surely fuels the engine of prayer. As we come to grips with how little we have valued the means of grace, even in worship, we will make greater use of them.
We have also, in the last few years, experienced some conflicts in the broader Reformed and Presbyterian world. There have been those who, seeing something of the poverty of our understanding and use of the means of grace, have placed an undue emphasis on their outward aspect. Some have spoken of baptismal regeneration and even embraced a view of the sacraments that sees them as virtually ex opere operato (conveying grace to all who do not positively refuse it). This lamentable externalism can lead to a deadly formalism that downplays the work of the Spirit, and it has been recognized as such by the OPC, the PCA, and others in NAPARC. Theological movements like Federal Vision (FV), whatever good they may have sought to do, have harmed the Reformed faith by an overly objectified sacramentalism that necessarily underplays the indispensable role of the Holy Spirit in making effectual the means of grace.
All this can lead, and has led in some quarters, to a backlash. Fear of FV, or fear of being considered FV, has prompted some to stake out positions on the opposite end of the spectrum and, particularly, to decry a high view of the sacraments. FV errors should not lead us to respond with Zwinglian views, but with solid, historic, confessional views. We should continue to recover a high biblical and confessional view of preaching and the sacraments—what Bill Shishko called "biblical high churchmanship" at a recent General Assembly. A right understanding of holy baptism is an important part of such a biblical position.
 Johannes G. Vos, in The Westminster Larger Catechism: A Commentary, ed. G. I. Williamson (Phillipsburg, NJ: P&R Publishing, 2002), pp. 474-75, notes that the word solemnly "is apparently used by the catechism in the sense of 'formally' or 'publicly.' That is, those persons who are already in God's sight members of the visible church by reason of their covenant standing (in the case of infants) or by reason of their own profession of faith in Christ and obedience to him (in the case of adults) are formally and publicly recognized as members—'solemnly admitted into the visible church'—by the sacrament of baptism."
 Vos, The Westminster Larger Catechism, p. 466.
 Even persons who do not profess faith can only be known to be unconverted; they cannot be known to be reprobate. While we may have an "infallible assurance of faith" (WCF 18.2)—based on our believing God's promises—and thus may inferentially know our election, no one is ever warranted in declaring that he himself or anyone else is reprobate (with biblical exceptions, such as Judas Iscariot). Rather, we are to seek to live in faith and obedience to God (Deut. 29:29).
 Vos, The Westminster Larger Catechism, p. 481.
The author, an OP minister, teaches at Mid-America Reformed Seminary. Reprinted from New Horizons, March 2008.