What I wish to do here is a relatively brief explanation of 1 Peter 3:18-22. This could well be the most difficult text in all of Scripture. It is dripping with difficulties.
18. For Christ also suffered for sins once and for all, the Righteous one on behalf of unrighteous ones, to bring us to God, having been put to death by men, but made alive by the Spirit, 19. By which also, having gone, He proclaimed to the spirits in prison. 20. They disobeyed long ago when God’s patience waited in the days of Noah, when the ark was being prepared, in which a few (that is, eight souls in all) were rescued through water: 21. this baptism (being an antitype to the water) now rescues you, not as an outward putting off of fleshly filth, but of an inward pledge to God of a good conscience: all this happens through the resurrection of Jesus Christ, 22. who, having gone into heaven, is at the right hand of God, having all angels, authorities, and powers subjected to him.
Overall picture and relevance: These can be combined and stated in several steps: 1. Peter is writing to suffering Christians. 2. In helping such suffering Christians, Peter wants to help them with the root of their persecution, which is demonic (or perceived to be demonic) in origin. 3. Christ conquered the demonic world through His death and resurrection. 3. Christians share in this victory through baptism (which means inclusion into the safety of the covenant). 4. Therefore, suffering Christians can be bold and gentle in sharing their faith and submissive to God in their endurance of persecution. In relation to the overall relevance, we can mention Eph. 6:12. Thus, we must qualify Christ’s victory as not implying eradication of the demons. We must still struggle (note the present tense feel of Eph. 6:12) with these demons. But the victory is ours through Jesus Christ, and does not belong to the demons.
Details of this victory:
Vs. 18: The textual variant “suffered” vs. “died” makes little difference in the context. Note here that Christ is not being shown as an example. This is proven by the words “once for all.” Rather, the focus is on the value of Christ’s actions for us. Note that “righteous” is singular (“the righteous person”), whereas “unrighteous” is plural (“the unrighteous people”). The Righteous One died on behalf of the unrighteous many. “Christ on behalf of us” is the meaning, clearly referring to the vicarious nature of the Atonement. “Bring us to God” has courtroom connotations. The verdict is “not guilty.” The circumstances under which Christ can bring us to God are the three aorist participles: “having been put to death,” “having been made alive,” and “having gone.” These are the conditions that had to exist in order for Christ to make us right with God. In other words, these three events happened BEFORE our courtroom appearance. Now, there are two possible interpretations of the parallel datives “in the flesh” and “in the (S)spirit.” They must be taken in a similar sense, since they are so obviously parallel. The first way is “in the sphere of.” However, the Greek distinction between body and soul is not within Peter’s thought here. I agree with Achtemeier, who thinks of the datives as instrumental, referring to being put to death by human flesh (human beings), but made alive by the Holy Spirit. If this is so, then Christ could not have come “in the spirit but minus His body” (this would be according to the Greek philosophical conception of the division of the person) in the three days between His death and resurrection. Rather, the proclamation took place AFTER His resurrection. In other words, Christ had body and soul together when He did the preaching.
Vs. 19. The “in which” refers most probably to the “spirit” mentioned just at the end of the previous verse. The ESV has left out the “also” that is supposed to be there right after the “in which.” This indicates a second activity that has been empowered by the Holy Spirit. The word “went” does not indicate a “descending into hell.” It is never used this way in the NT. Another word is used for that in Eph. 4:9, and Rom. 10:6. I think (with Dalton and Achtemeier) that the ascension is the reference here. Jesus went after Ascension but before Session at the right hand of God. I do think it is possible, however, that Christ did not actually preach in person to the spirits. The “in which” might give some extra credence to this possibility. The word “proclaimed” here usually means that the gospel is the content of the preaching. However, this is not always the case. The basic root meaning is “to be a herald.” Thus, this word cannot be forced into meaning that the spirits have another chance at salvation. Now, who are the spirits? Grudem would claim that it still could be humans, if you understand the phrase to mean “those who are now spirits.” A parallel to this would be to say that Queen Elizabeth was born in 1926, even though she did not become queen until much later. However, why is only the flood generation of people mentioned? This difficulty is much lessened when we understand “demons” by the word “spirits.” First of all, the word in the plural almost always refers to demons. If it does not, then there is always some form of qualification, which there is not in this case. Second, the reference to the disobedience is probably dependant on the tradition of 1 Enoch. 1 Enoch thought of the people’s disobedience in Noah’s time as dependant on the demons’ disobedience, to such an extent that the demons were thought to cause the Flood by their extreme disobedience. Thirdly, if it refers to people, then how does a knowledge of Christ’s preaching to people encourage people in suffering? Remember also that Christ’s actions here are not examples, but one-time occurrences. Now, not all the phrases in 1 Peter refer to demons. “In prison” must refer to the demons. This is a further argument that they are demons. This word does not refer to the place where human souls are kept. The reference is rather to a place “under guard.” Since when are people’s souls (and in this case, they would be saved, since the message would have to be salvation) kept under guard?
Vs. 20 The next phrase also refers to the demons. It can be translated “because,” or “when.” “Formerly did not obey” obviously refers to the spirits. This (I believe) refers to the Enoch tradition as to how they disobeyed. Peter is making a literary allusion (and so not necessarily endorsing 1 Enoch’s view) to 1 Enoch’s view of Genesis 6:1ff. 1 Enoch interpreted the “sons of God” as being angels, who disobeyed God’s order not to mess with human women. As a result, they generated a race of giants, the “Nephilim.” This interpretation of Genesis 6 in 1 Enoch is not the same as Peter’s. Peter is merely invoking 1 Enoch to make the point that even the most radically powerful and evil spirits have been conquered by Christ. See especially 2 Peter 2:4 and Jude 6. The next phrase (“that is, eight souls) has been taken by some as conclusive that the spirits must be human souls. However, I do not think it is necessary to see this phrase as referring to the spirits of humans. It is possible that the phrase refers to both spirits and human beings, or just to human beings. The point here for Peter is to nail down the exact time. There is a parallel between that time and now. God’s patience is also waiting now while the elect are being gathered, and the wicked are increasing their wickedness. The next phrase (“in the days of Noah, when the ark was being prepared”) does not necessarily refer to the building of the ark. If the reference to 1 Enoch is finished with the previous phrases, then it might be possible that the preparing refers to all the animals being gathered. It is possibly then a divine passive (God doing this “preparing”). The only other thing that needs comment in this verse is the last phrase. I am not sure that the ESV has correctly translated it. The Flood was the means whereby Noah was saved from the pagan environment. As such, the Flood is ironic. It is extremely destructive, and yet God brought about His saving purposes through it. I believe that is the meaning of the last part of this verse.
Vs. 21 Does this verse imply baptismal regeneration? Yes, it saves, but from what? The evil dominion of the spirits! Baptism involves the person in the victory achieved over the spirits by Christ’s death and resurrection. The negative qualifier indicates that baptism is not just an outward sign of inclusion into God’s covenant. It is that, but it is also much more than that. (I disagree with Dalton here: I do not think that circumcision is meant). We tend to devalue baptism in Presbyterian circles. We should not do this. Baptism gives us a clean conscience with regard to demons. It symbolizes the blood of Christ that cleanses us from our sins. One of those benefits of inclusion into the community of God’s people is freedom from demonic tyranny.
Baptism is related to the Flood in an antitypical manner. The Flood simultaneously destroyed wickedness, and saved Noah from that wicked environment. Baptism is symbolic of the destruction of the demons, and of our freedom from their influence.
Vs. 22 This verse caps the entire pericope by stating again the grounds upon which our hope is built. Christ has conquered sin and death, and sits with angels and principalities under His feet. This is probably a reference to Psalm 110:1.
It should be mentioned that this interpretation has been stated rather forcefully. I do not think we can be dogmatic about this interpretation. Indeed, you may choose to believe Augustine’s interpretation, which I think is the only viable option for the Reformed camp. Nevertheless, I think that Achtemeier, Dalton, and Kelly are correct in their overall interpretation. I think it makes the most sense of the context, and is actually the most practical for Peter’s readers. Practicality for us can be along the same lines. We either dismiss the demonic world too easily, or we fear it too much. I think Peter has much to say on both counts.