(a) what is the topic of 1cor 12:4-27 and 13:8-13?
The main topic that Paul has in mind in both chapters is what Christian spiritual life1) should be understood and practiced, considering the Corinthian perverted understanding and practice of spirituality which made them 'puff up' and divisive by claiming the superiority of a particular spirituality over against others. For this reason Paul's intention in both chapters is corrective rather than instructional or informational.2) His corrective answer is that Christian spiritual life requires diversity in unity, aims at building up the church, and must be practiced by love as the permanent source and relativizing principle for the Christian practices of spirituality in the present and the future.
In 1cor 12:4-27 Paul asserts that Christian spiritual life requires the necessity of 'diversity manifested within unity', over against a Corinthian tendency of 'uniformity among diversity,' for the purpose of building up the wholesome church. This chapter can be divided into two sections: vv. 4-11 and vv. 12-27. In the first section Paul corrects Corinthians' singular enthusiasm concerning their own spiritual gift, esp. the gift of tongues, by appealing to the nature of the divine activities, i.e., the divine sovereignty to distribute each believer diverse gifts "as he pleases" (v.11), and to the purpose of giving them spiritual resources, i.e., the purpose "for the common good" (v.7). In the second Paul reinforces all this by making use of the 'body' analogy which emphasizes the interconnectedness and uniqueness of individual members (vv. 14-26) and their belonging to Christ and the faith community through the Spirit (vv. 12-3, 27).
In 1cor 13:8-13, based upon his eschatological vision, Paul suggests love as the permanent source (vv. 8, 12, 13) and relativizing principle (vv. 9-11) for the Christian practices of spirituality while bestowing the spiritual gifts the temporary value valid only to the present and relativizing all knowledge of God obtained by the gifts as fragmentary and perishable. Through chapters 12 and 13 Paul redirects the Corinthian perverted understanding and practice of spirituality by explaining what Christian spiritual life should be understood and practiced (in the present and toward the eschaton).
(b) what 12:12-14 discloses about Paul's understanding of baptism (cf. 1:30; 6:11; 10:1-5)
The emphasis in vv. 12-4 is not on baptism as a rite but on Corinthians' shared experience of the one and the same Spirit and therefore on their belonging to (the body of) Christ. The evidences for this are: first, there is no reference to 'water'; second, Paul bestows baptism as a metaphorical meaning to enter "into one body"; third, he indicates that the members of the body comes from the religious/social diversity in the Corinthian church such as "Jews or Greeks, slaves or free"; and finally he explains baptism in a metaphorical sense as drinking "one Spirit". The comparisons with other passages such as 1:30; 6:11; 10:1-5 also support the argument.
In 1cor 1:30 Paul asserts that the source of Christian life is Jesus Christ by whom we are given the undeserved right stance toward God ("righteousness"), called into a new faith community ("sanctification"), and delivered from sin ("redemption"). The whole nuance of this is, "You (Corinthians) belong to Jesus.
Paul addresses in 6:11: "But you were washed, you were sanctified, you were justified in the name of the Lord Jesus Christ and the Spirit of our God." The expressions "washed" and "in the name of..." remind us of baptism terminologies. However, Paul's intention here is to indicate that Christian faith requires the transformed practice when he considers that Corinthians still remained in their previous habits of behavior and did not reflect whether their life was in conformity to the standards of their new community.
Especially in conjunction with "drinking one Spirit" (12:13) there appears a corresponding passage in 10:17, "Because there is one bread, we who are many are one body, for we all partake of the one bread." In this passage the practice of the common meal is metaphorically used for each individual believer's making up the body of Christ rather than defining what the Lord's Supper should be practiced. Based upon the context of 12:12-4 and the comparisons with other passages such as, 1:30; 6:11; 10:1-5, Paul's reference to baptism connotes Corinthians' shared experience of the one and the same Spirit and therefore on their belonging to (the body of) Christ.
(c) what chapter 12 as a whole discloses about Paul's view of the Spirit (cf. chapter 2)
Before stating the inspired gifts by the Spirit in 12:4-11, Paul establishes the bottom line of the inspiration of the Spirit as the shared confession that "Jesus is Lord" (v. 3). This implies that Corinthian believers seems to judge themselves and others according to their own wisdom or knowledge, formed previously or quasi-christianly, which misses the focal point of what the inspiration of the Spirit is like.
Indeed, Paul begins with an indication that Corinthians before conversion were in idolatry (v.2). At that time they could be inspired by other spirit(s). For Paul, what distinguishes Christian inspiration from other is the shared faith in Jesus Christ as the Lord. This faith is not simply a matter of individual believing. Rather it has to do with how a Christian must understand and form her/his spiritual life in the new community which is in relationship to Christ the crucified and risen Lord. In this context, Paul asserts that the Spirit inspires each believer to confess Jesus Christ as the Lord (v. 3) and to be given diverse gifts, services, and workings (vv. 4-10), in order to use them "for the common good" (v. 7).
In chapter 2 Paul mentions that Christians are the existents inspired by the Spirit, not by the worldly spirit(s) [2:12]. The main point of the divine inspiration by the Spirit is to make Christians possess "the mind of Christ" (2:16) who was crucified on the cross (2:2) and to understand all spiritual gifts according to this mind (2:10-16). Paul seems to acknowledge that Corinthians were inspired by the Spirit (2:12-3). Corinthians' problem is to understand such inspiration according to their own standards, formed previously or quasi-christianly, that they boasted themselves and made divisions in community. For this reason all inspired gifts must be tested by "the mind of Christ" the crucified and risen so that they be transformed fully Christianly.
Paul's common view of the Spirit in both chapters 12 and 2 is that Christians in a genuine sense are transformed in self-understanding, in that they are inspired by the Spirit to enter the new community which confesses Jesus Christ as the crucified and risen Lord, and in practice, in that they are inspired by the Spirit to behave christianly according to their faith relationship to God in Christ through the Spirit.
(d) what 13:8-12 has in common with 8:1-3
From his eschatological stance Paul defines in 1cor 13:8-13 that love is valid not only in the present but in the future while the spiritual gifts, such as prophecies, knowledges, tongues, are valid in the present. Why does love persist while the inspired gifts perish? The answer to this question are not hinted in 1cor 13:8-12 but sought by connection with 1cor 8:1-3. In 1cor 8:1-3 Paul maintains, "Knowledge puffs up but love builds up" (8:1). This implies that knowledge has no power to relativize and direct itself to the edification while love does have.
However, a question still remains, "Then, why is knowledge unable to possess such power?" Paul's answer is that human knowledge reveals its fragmentariness (13:8, 12) while love as our faith relationship to God entails "the necessary knowledge" which uncovers that a human being know God partially and is known by God perfectly (8:3). For this reason our loving God relativizes and redirects our knowledge in a transforming way. Likewise, love as our relationship to God relativizes and redirects all the inspired gifts for building up the church. In this respect, love as our faithful relationship to God is the relativizing principle and the directing principle for Christian spiritual life to build up the church.
1) What I here mean by the term 'spiritual' includes not only the Corinthians' spiritual phenomena, such as spiritual experiences and gifts, but their religious, social, and political status, such as the state of Jews or Gentiles, free citizens or slaves.
2) See The First Epistle To The Corinthians (Grand Rapids, Michigan: William B. Publishing Company, 1987), Gordon D. Fee, p. 570.