Verses 5-7 explain in rich detail and from several perspectives the nature of the salvation that this event brought.
Salvation and God's mercy (3:5). First, the cause of our salvation is solely God's mercy. While from the standpoint of human need Jesus' crucifixion could be explained as "for our sins" (1 Cor 15:3), from the standpoint of God's love it was because of his mercy. This mercy of God is the equivalent of the loving-kindness of God that in the Old Testament (Hebrew hesed) formed the basis of the covenant relationship with Israel. Salvation in Christ has its origin in the very same place. It is God reaching toward humankind to put us into relation with himself, not (as the phrase not because of righteous things we had done shows) the reverse. Human effort is excluded: salvation is not something that a person can merit (Rom 3:21-28; Gal 3:3-9; Eph 2:8-9; 2 Tim 1:9).
Salvation and the Holy Spirit (3:5-6). Second, it is the Holy Spirit who applies salvation to us. But the three metaphors that occur in this connection—washing, rebirth and renewal—require a closer look. If you have been in the church for a while, you probably feel comfortable with such terms; they have become Christian jargon, and we hardly question their meaning. In fact, though, such words put off outsiders to the faith, and our frequent easy use of such jargon leaves them rightly wondering whether we really do understand what we believe.
A check of the commentaries confirms that the meanings of these words and their relationships are not settled matters. The main possibilities can be arranged as follows (see Dunn 1970:165-70 and Fee 1988:204-5).
1. through the washing of rebirth
(through) renewal by the Holy Spirit
2. through the washing that produces rebirth and renewal,
(the washing being) by the operation of the Holy Spirit
Arrangement 1 above has two separate events in mind: Roman Catholic commentators divide them into baptism and confirmation (others take them as conversion and confirmation), but some groups have seen in this arrangement a reference to conversion and a subsequent baptism in the Holy Spirit.
Arrangement 2 can be taken as a reference to baptism, during which or through which rebirth and renewal occur, the Holy Spirit being the agent of washing. Or 2 can be taken as a reference to the conversion/initiation event in which the individual receives the Spirit and is thus cleansed, reborn, renewed and incorporated into the community of faith. Either way, one (more complex) event—washing by the Spirit—is envisaged.
While it is well to keep in mind that these verses represent a liturgical formulation and are therefore not necessarily meant to be precise statements of theology, the following points speak against interpretation 1 (two separate activities) and favor 2 (one complex activity). First, the two metaphors, rebirth (palingenesia) and renewal (anakainosis) are practically synonyms and thus express a unity. This is even more likely since there is just the single preposition through governing the phrase; ordinarily, where two conceptually related ideas are involved yet two separate activities are meant, the preposition would be repeated to ensure that the distinction is made by the reader. Then the reference to the outpouring of the Spirit in verse 6, an allusion to Pentecost (see below), suggests that the role of the Spirit is central in the thinking of verse 5—thus it is probably best to understand verse 5 as referring to one event of washing by the Spirit which produces two closely related effects, rebirth and renewal.
In other words, the tradition Paul draws on at this point seeks to emphasize the gift of the Spirit in the salvation process. And based on verse 6, which takes up the traditional imagery of washing and water in poured out to describe the Spirit's life-giving and renewing work, the reference to washing (loutron) in verse 5 is most likely a reference to spiritual washing rather than to the rite of water baptism (compare Eph 5:25-27).
Rebirth and renewal describe the work of the Spirit. Rebirth is a coming back to life from death, an apt description of the new life in contrast to the old one of sin and death (v. 3; on the Spirit and [re]birth see Gal 4:29; 1 Cor 4:15 with 2:4). As explained in Romans 6:4-11 and Philippians 3, by faith in Christ one is enabled to participate in Christ's resurrection life even now. Renewal expresses almost synonymously the idea of "re-creation" (compare 2 Cor 5:17). These two terms bring together the whole change associated with conversion and life in the new age of salvation—restored fellowship with God and new, eternal life.
Salvation and history (3:6). Verse 6 spells out in greater detail the historical reference point of salvation alluded to in verse 4 (when . . . appeared). It consists of two things. First, the verb poured out takes the readers back to the description of the outpouring of the Spirit on the day of Pentecost (Acts 2:17-18, 33). Second, verse 6 brings the thought back to the work of Christ, through which God's plan became concrete reality. The phrase through Jesus Christ our Savior is an abbreviation for Christ's historical ministry of teaching, healing, sacrificial death and resurrection, and its results (v. 5). As the preposition through indicates, it was this Person and his work that made possible the gift of the Holy Spirit (Jn 16:7; Acts 2:33).
The whole passage has been establishing the basis for a new way of life (vv. 1-2), and it is a historical basis. The perspective from which the new possibility is viewed is that of salvation history, God's kingdom intersecting time and space: verses 3 and 4 announce the great turning point for human ethics—Christ's appearance. God the Father (vv. 4-5), the Holy Spirit (vv. 5-6) and Jesus Christ (vv. 4, 6) are joined together in the work of salvation (compare 1 Cor 12:4-6; Eph 1:3-14; 4:4-6).
Salvation and justification (3:7). Paul's material views salvation from one more familiar perspective, justification by grace. Justification, as it is often pointed out, is salvation seen from a forensic or legal perspective. It is the judge's declaration of righteousness. But the grounds are not that the defendant has been found to be free of guilt. Rather, the defendant's guilt has been paid for by another—Christ—and so it is a matter of grace, an unmerited participation in Christ's righteousness. Paul often coordinates salvation and justification or uses the terms almost synonymously (Rom 10:10). Sometimes he maintains a distinction between them, making the "righteousness of God" the understood condition for receiving the gift of salvation. This is probably the intention here.
Salvation and hope (3:7). What is the goal of God's redemptive work? It is eternal life (Rom 2:7; 5:21; 6:22-23; Gal 6:8). Through justification, the believer takes up the privileged position of an heir, as Paul often points out (Rom 3:24; 4:13-14; Gal 3:6-29; 4:6-7). The unique thing about God's family is that every Christian shares this position equally. None is entitled to a greater share than another, for the object of inheritance is eternal life (compare Mt 19:29; Lk 18:18). But the inheritance is yet to be received, so it remains an object of hope. Nevertheless, the certainty of God's past acts in Christ guarantees the certainty of what is still to be fully obtained (see above on 1:2).
Consequently, Christians can boldly live the kind of life prescribed in verses 1 and 2, because God has intervened in human history to bring about a change. The whole salvation complex—rebirth and renewal, justification and hope—is reality, grounded in the historical events of Christ's ministry and death/resurrection and in the outpouring of the Holy Spirit. But to experience the new reality, the believer must actively decide to step forward; the reality of the Christian possibility is not experienced through reciting a creed but by performing it in faith.