This passage in I Peter 3, particularly verses 19-20, is quite difficult to translate from Greek to English. This is so because each of the nine Greek words in verse 19 can be translated in various shades of meaning, making interpretation tricky. We probably do best by translating them in their most basic meanings, thus: "in which also He went and proclaimed to the spirits in prison . . ." (author's paraphrase).
The "which" ("whom" in NKJV) in verse 19 probably refers back to "Spirit," its closest antecedent, in verse 18, suggesting that Jesus was no longer in the flesh but by this time had been changed into spirit. This follows the historical chain of events in order from the preceding verse: He suffered, died, was resurrected, and was thus changed to spirit, leading to the next key words, "He went."
What happened next in the gospel record after His resurrection to spirit? What did Jesus do after arising from the dead? Some might suggest that He revealed Himself to His disciples, which He did, but not by any stretch of meaning could it be described as going and proclaiming to imprisoned spirits! No, John tells us through the words of Jesus Himself to Mary Magdalene what the next momentous occurrence was: "[G]o to My brethren and say to them, 'I am ascending to My Father and your Father, and to My God and your God'" (John 20:17). When Jesus "went," He ascended in glory to the right hand of the Father in heaven!
At this point, we will skip to the phrase "spirits in prison." First, let us note that the Bible does not refer to human beings who have died as being imprisoned in any way, not even those who have rebelled against and rejected God. They may be said to be "destroyed" or "killed" or "cut off" or sent to "Sheol," which is a pit or grave, but they are never imprisoned. As we saw, humans who die return to the dust of which they are made (see also Genesis 3:19; Ecclesiastes 3:19-20).
However, the Bible speaks in several places about spirit beings - angels or demons - being imprisoned (see II Peter 2:4-5, where Peter again refers to Noah's time; Jude 6; and Revelation 20:1-3, 7). Rebellious angels, unlike mortal humans, must be imprisoned because angels or demons, being composed of spirit, do not die as humans do. The "angels who sinned," Peter and Jude say, were cast down to Tartarus ("a place of restraint," a prison) where they are bound until God judges them. This Tartarus, this "hell" where the demons are restrained, is none other than their "first estate," their "proper domain," earth (see Ezekiel 28:17; Revelation 12:7-9)!
Second, Peter's use of "spirits" is consistent with its use in the gospels (see, for instance, Matthew 8:16; 12:45; Mark 3:11; 5:13; 6:7; Luke 11:26; etc.). In the gospels, "spirits" consistently denotes "evil spirits," "demons," "wicked spirits." It is highly likely that Peter refers to demons in I Peter 3:19.
This is confirmed by the first phrase of verse 20, "who formerly were disobedient" (NKJV) or "who disobeyed long ago" (New International Version, [NIV]). Peter is speaking of a time in deep antiquity, a time before the Flood. Perhaps he does not intend us to think of Satan's original sin of rebellion against God (Isaiah 14; Ezekiel 28), although it may be included, but specifically of the demons' corruption of mankind between the Creation and the Flood.
This would explain his time marker in the next phrase, "when God waited patiently in the days of Noah while the ark was being built" (NIV). In Satan's sin, only the demons themselves were affected, but when they corrupted mankind, human beings who were potential sons of God were affected. Once men and women began sinning under the influence of Satan and his demon horde, the sacrificial death of Jesus Christ became necessary.
Peter's point, then, is that, though the wicked spirits seemed to be so successful in corrupting mankind, God patiently waited during Noah's 120-year ministry to save only eight people by bringing them through the Flood, delivering them through a kind of baptism. The demons had failed to destroy mankind. So also, by having Jesus crucified, the demons thought again they had won, but through the resurrection, Jesus had the victory instead. Baptism is a type of this same victory, as it is a symbolic death of the old, wicked man and of his resurrection to newness of life (see Romans 6:4).
This brings us back to the word in I Peter 3:19 that we skipped: "proclaimed" (or in many Bibles, "preached"). Most objective commentaries will note that this word in the Greek (ekêruxen from kêrússô) means in general "to be a herald," "to proclaim," "to announce," "to publish," "to preach." Although it can be used as such, it does not necessarily mean "to preach the gospel to" or "to preach salvation to." Because Peter does not specify what Jesus "proclaimed" or "announced," to assume the preaching of the gospel is not warranted. The only clue we have of what He proclaimed appears in the immediate context: that He was "made alive by the Spirit."
If this is the case, verse 19 says simply that, after Jesus was resurrected, He ascended to heaven, proclaiming to the imprisoned evil spirits that He lived! The demons, once again, had failed!
Verse 22 backs this interpretation: "who has gone into heaven and is at the right hand of God, angels and authorities and powers having been made subject to him." This agrees with many scriptures that speak of His exaltation over all things, for instance, Philippians 2:9-10: "Therefore God also has highly exalted Him and given Him the name which is above every name, that at the name of Jesus every knee should bow, of those in heaven, and of those on earth, and of those under the earth." Jesus' ascension to the throne of God proclaimed His victory over death and over Satan and his demons!