For just as the body is one and has many members, and all the members of the body, though many, are one body, so it is with Christ. For in one Spirit we were all baptized into one body – Jews or Greeks, slaves or free – and all were made to drink of one Spirit.
1 Corinthians 12:12-13
Paul had just explained to the brethren at Corinth that the Holy Spirit had given some of them different kinds of miraculous spiritual gifts, and had chosen which gift or gifts to give to each one of them based on his, the Spirit’s, own divine will (12:4-11). There was division in Corinth over these spiritual gifts in that some of them coveted miraculous gifts which they themselves did not possess and which God had given to others (14:1-40). The apostle wanted them to understand that those among them who had a particular spiritual gift had been given that gift for a reason, and thus should not be jealous of his brother or sister who had a different gift.
To illustrate his point, Paul compares the body of Christ to a human physical body. He starts by pointing out that the church has many members who are all part of Christ’s body (12:12). Regardless of their ethnicity (“Jews or Greeks”) or social status (“slaves or free”), they all were part of Christ’s body (12:13b). Since Christ’s body is his church (Col. 1:18; Eph. 1:22-23), Paul’s point is that all Christians, including everyone in the church at Corinth regardless of what miraculous spiritual gift they possessed, were part of the church which belongs to their Lord.
They had become part of the body of Christ when they were baptized into it (12:13a). Paul’s statement, “For in one Spirit we were all baptized into one body” refers to when they believed and obeyed the Holy Spirit-inspired gospel of Christ which commands baptism as part of God’s plan of salvation (2 Pet. 1:19-21; Eph. 3:3-5; 1 Cor. 2:9-16; Acts 2:4, 36-39, 41-42, 47; Tit. 3:3-5; John 3:3-5; Mk. 16:15-16). His subsequent statement that “all were made to drink of one Spirit” upon being baptized into Christ’s body refers to the fact that they had received the Holy Spirit at their baptism (12:13c; cf. Acts 2:38-39; 5:32; 8:9-11).
It’s worth noticing that Paul says that “we were all baptized into one body” (12:13, emphasis mine). He elsewhere specifically defines the body of Christ as Christ’s church (Col. 1:18; Eph. 1:22-23) while also specifying that there is only “one body” as well as “one baptism” and “one faith” (Eph. 4:4-5). If there is only one body of Christ (Eph. 4:4), and the body of Christ is his church (Col. 1:18; Eph. 1:22-23), then that means there is only one church in the sight of God.
With this in mind, we should notice that Paul and the other New Testament writers join the Lord Jesus in warning repeatedly of apostasy and false teachers who would lead disciples astray (Matt. 7:15-16a, 21-24, 26; Acts 15:1ff; Rom. 1-11; 16:17-18; 1 Cor. 7:18-19; 2 Cor. 3:3-11; 11:13-15; Gal. 1:6-10; Eph. 2:1-22; Col. 2:8-23; 2 Thess. 2:1-12; 1 Tim. 1:3-11; 4:1-7; 6:3-6, 20-21; 2 Tim. 2:14-26; 3:1-13; 4:1-5; Tit. 1:9-2:1; 3:9-11; James 5:19-20; 2 Pet. 2:1-22; 3:3-5, 15-16; 1 John 1:8, 10; 2:4, 18-27; 4:1-6; 2 John 7-11; Jude 3-16; Rev. 2:2, 9, 14-16, 20-24; 3:9; 13:1-18; 19:20; 20:10; 21:8, 27; 22:15, 18-19). This becomes significant in light of the fact that in God’s eyes there is only “one faith” (Eph. 4:5), and that faith comes solely from God’s Word (Rom. 10:17). History shows us that the reason there are 45,000+ different churches which all proclaim allegiance to Christ while teaching and following different faiths and doctrines is due to the desire to follow the teachings of man rather than the teachings of God which are found only in Scripture (2 Tim. 4:1-5).
Therefore, Paul’s statement that “we were all baptized into one body” (12:13) – the singular body of Christ which is his church (Col. 1:18; Eph. 1:22-23), the only church which God recognizes (Eph. 4:4-5) – is even more significant. If we want to receive salvation through God’s grace, we must be baptized into that one body which is the one church which belongs to Christ. That is the “one baptism” which God recognizes (Eph. 4:5).
— Jon