Many Parts, One Body (12:12)
Now Paul introduces the analogy of a body that explains unity through diversity, how each very different person and gift goes into making a healthy, capable, well-rounded body.
"The body is a unit, though it is made up of many parts and though all its parts are many, they form one body. So it is with Christ." (12:12)
Just as a human body has many parts and organs, so does Paul's analogy to Christ's body, the church.
Baptized by the Spirit into Christ's Body (12:13)
Baptism is the introduction to being a part of the church -- and a "member" of Christ.
"For we were all baptized by one Spirit into one body -- whether Jews or Greeks, slave or free -- and we were all given the one Spirit to drink." (12:13)
The Baptizer in this analogy is the Holy Spirit -- He is the one through whom we come to faith and to water baptism. And when we become Christians, that is, members of Christ's body, we are indwelt by the Holy Spirit, or, as Paul puts it here, "given the one Spirit to drink."
Notice, Paul isn't speaking of an experience of some, but of all believers. Though some of my Pentecostal brothers and sisters may disagree with me at this point, I don't believe Paul is speaking here of the "baptism of the Holy Spirit" as a second work of grace. I believe Paul is speaking of our initial salvation and continuing life in Christ, in the same sense that Paul talks about it in other letters.
"If anyone does not have the Spirit of Christ, he does not belong to Christ." (Romans 8:9)
"He saved us, not because of righteous things we had done, but because of his mercy. He saved us through the washing of rebirth and renewal by the Holy Spirit." (Titus 3:5)
Paul is stressing the unifying action of the Spirit here to a church that has divisions. The Spirit unites all -- Jew or Greek, slave or free. Paul says it in a similar way to the Galatian church:
"You are all sons of God through faith in Christ Jesus, for all of you who were baptized into Christ have clothed yourselves with Christ. There is neither Jew nor Greek, slave nor free, male nor female, for you are all one in Christ Jesus." (Galatians 3:26-28)
The Body Is Made Up of Many Essential Parts (12:14-17)
The Corinthians were over-emphasizing speaking in tongues and under-emphasizing prophecy. So Paul says that each part is important. It is not only the tongue-speakers that are part of this body.
"14 Now the body is not made up of one part but of many. 15 If the foot should say, 'Because I am not a hand, I do not belong to the body,' it would not for that reason cease to be part of the body. 16 And if the ear should say, 'Because I am not an eye, I do not belong to the body,' it would not for that reason cease to be part of the body. 17 If the whole body were an eye, where would the sense of hearing be? If the whole body were an ear, where would the sense of smell be?" (12:14-17)