Well Alex, that thread you posted seems to make a connection to what octoberose is asking about. What was brought out in that thread concerns the "angels of the Devil," where Ray showed rather convincingly in his '23 Minutes in Hell" article that 'angels' in Scripture is never speaking of demon spirits. So as the passage octoberose is asking about is speaking of "the spirits now in prison," is related.
1Peter 3:18 For Christ also suffered once for sins, the righteous for the unrighteous, that He might bring us to God, being put to death in the flesh but made alive in the spirit,
v. 19 in which He went and proclaimed (preached) to the spirits(H4151 pneuma) in prison,
v. 20 because they formerly did not obey, when God's patience waited in the days of Noah, while the ark was being prepared, in which a few, that is, eight persons, were brought safely through water.
In verse 19 the phrase "in which He (Christ's Spirit) went," which is the same Spirit of Christ, as it had just spoken in the verse before, that Christ was "...made alive in the Spirit, in which..." so speaking of the same Spirit.
It goes on to say, "He (His Spirit) went and proclaimed/preached..." and when was it He preached? Next verse gives the period reference as long ago "in the days of Noah, while the ark was being prepared," not while Christ was in the tomb, but it's talking about back in the days of Noah. And we can deduce it was speaking of the Spirit of Christ preaching through Noah, "a preacher of righteousness." Noah was a "preacher" and Peter says that the ancient prophets spoke through and were influenced by the "Spirit of Christ" (1 Peter 1:11). Going to a passage is in 2 Peter, that helps a lot with this passage.
2Peter 2:4 For if God did not spare the angelsG32 (Strong's aggelos - a messenger; especially an “angel”; by implication a pastor: - angel, messenger.) who sinned, but cast them down to hell (the grave) and delivered them into chains of darkness, to be reserved for judgment;
v. 5 and did not spare the ancient world, but saved Noah, one of eight people, a preacher of righteousness, bringing in the flood on the world of the ungodly;
There in verse 4 "the angels" is specifically what Ray brought out in the '23 Minutes in Hell' article that this is NOT speaking of spirit beings, but physical preachers. So, when Noah "preached", warning those people of the coming judgment of the flood, he spoke by the Spirit of Christ and these "spirits (preachers) who sinned" are maybe those back in v. 19 "the spirits in prison," or false preachers of Noah's day, who spoke against the truth that Noah was preaching?
Anyway I hope that is understandable, just wanted to show there may be a connection in these two passages.
mercy, peace and love
Kat