"WHERE WAS JESUS DURING THE THREE DAYS BETWEEN HIS DEATH AND RESURRECTION?"
1Peter 3:18-20 is a difficult passage of Scripture.
v18 "For Christ also hath once suffered for sins, the just for the unjust, that he might bring us to God, being put to death in the flesh, but quickened by the Spirit: v19 By which also he went and preached unto the spirits in prison; v20 Which sometime were disobedient, when once the longsuffering of God waited in the days of Noah, while the ark was a preparing, wherein few, that is, eight souls were saved by water."

Modern translations are no help at all. In fact, they make common sense interpretation much more difficult: "For Christ also died for sins once for all, the just for the unjust, in order that He might bring us to God, having been put to death in the flesh, but made alive in the spirit." (NASV)

"Christ also died for sins?" We agree. But what has that got to do with this passage of Scripture? There was no talk of dying for sins, only suffering for sins. Peter said that Christ also suffered for sins, the just for the unjust. But when the modern translators insert something like "Christ also died for sins,..." they are muddying up the waters. If Christ also died for sins, that says that someone else died for sins as well. Who? Was he also just for the unjust? We don't need scholars to answer that. Clearly that addition doesn't belong there.
There is another error here, and it is a glaring one. Christ was put to death in the flesh, that's true, but if He was "made alive in the spirit," after being put to death in the flesh, then it means that He had been dead in the spirit, and such a statementis is as near to blasphemy as it can get. Why the Bible was changed to say such a thing is beyond comprehension. Jesus Christ was put to death in the flesh, but quickened (made alive) BY the Holy Spirit. There is no mystery here. Just read the KJV to get the true piture.

Verse 19 has prompted some strange interpretations. The "improvements" by the NASV are, once again, quite negative. "in whom also He went and made proclamation to the spirits now in prison." Christ didn't preach to the prioners IN the Spirit; He preached to the prisoners BY the Spirit.

WHO WERE THE SPIRITS

It is argued, not entirely without legitimacy, that people are not spirits, that angels and demons and such are spirits. That is almost the whole truth, but not quite. These Scriptures indicate the posibility that spirit is part of man, and the two may be inseparable:

1Corinthians 12:10 "To another the working of miracles; to another prophecy; to another discerning of spirits; to another [divers] kinds of tongues; to another the interpretation of tongues": How can a mere mortal discern spirits if they are angels or demons? Luke 11:26 "Then goeth he, and taketh [to him] seven other spirits more wicked than himself; and they enter in, and dwell there: and the last [state] of that man is worse than the first." 1Corinthians 14:32 "And the spirits of the prophets are subject to the prophets." Hebrews 12:23 "To the general assembly and church of the firstborn, which are written in heaven, and to God the Judge of all, and to the spirits of just men made perfect," 1John 4:1 "Beloved, believe not every spirit, but try the spirits whether they are of God: because many false prophets are gone out into the world."
WHERE WERE THE SPIRITS, AND WHAT DID CHRIST PREACH TO THEM?

The assumption, widely believed, is that these "spirits" were the spirits of the departed in hell, or in Hades, or some other place where sinners await final judgement. Now, of course, the Bible does not say what "sermons" the spirit of Christ was supposed to have preached to them, so imaginative Bible teachers are free to conjure up all sorts of stories, some more bizarre than others. Some believe that the spirit of Christ preached through Noah while he was building the ark.

Verse 20 is, admittedly, a difficult verse, even as rendered in the KJV. It would seem that Christ preached, and God patiently waited, while the ark was being built, while only eight souls were saved by water. Read verse 20 carefully. Peter does not say that Christ preached to those spirits while the ark was a building. Verse 21 offers a clue. The phrase, "...The like figure..." is the key. Peter was using the Noah scenario as an example of what was going on in his own(Peter's) day, in which day God was patiently waiting while the people were going through the "Baptism of fire," a purging process to prove the faithfulness of those Jews who professed faith in Christ, and weed out the disobedient. Several times in the Bible that time period is referred to as "tribulation," but not the Great Tribulation. Out of the multitudes of Israelites, relatively few would be saved, the same as in Noah's day.

But who were those "spirits in prison" that Christ preached to by the Spirit? They weren't in hell; they were the "lost sheep" of Israel, living in "outer darkness," walking the streets of Jerusalem, and the countryside of Judea. Before Jesus began His ministry, He went into a synagogue, and read from the book of Isaiah. Luke 4: v18 "The Spirit of the Lord is upon me, because he hath anointed me to preach the gospel to the poor; he hath sent me to heal the brokenhearted, to preach deliverance to the captives, and recovering of sight to the blind, to set at liberty them that are bruised," v19 "To preach the acceptable year of the Lord." v20 "And he closed the book, and he gave it again to the minister, and sat down. And the eyes of all them that were in the synagogue were fastened on him." v21 "And he began to say unto them, This day is this scripture fulfilled in your ears."

So Jesus did not go "down" when He died; He went up. Luke 23:46 "And when Jesus had cried with a loud voice, he said, Father, into thy hands I commend my spirit: and having said thus, he gave up the ghost."
What did He do up there? That was an event which I believe Daniel foresaw years before it happened: Daniel 7:13 "I saw in the night visions, and, behold, one like the Son of man came with the clouds of heaven, and came to the Ancient of days, and they brought him near before him. v14 And there was given him dominion, and glory, and a kingdom, that all people, nations, and languages, should serve him: his dominion is an everlasting dominion, which shall not pass away, and his kingdom that which shall not be destroyed."

I don't know of any other time that could have happened, because when He rose from the dead, His Father had given Him all the power in the whole universe (Matthew 28:18). That's a lot of power! Romans 1:3 "Concerning his Son Jesus Christ our Lord, which was made of the seed of David according to the flesh; v4 And declared to be the Son of God with power, according to the spirit of holiness, by the resurrection from the dead:"

WHY DID PETER USE THE TERM "SPIRITS" WHEN REFERRING TO THE PEOPLE OF NOAH'S DAY?
I, for one, do not know. I think it may have something to do with the fact that, collectively, there was a strong spirit of disobedience among the people back in Noah's day as well as in Peter's day. In fact, the one trait by which the Israelites could be known was the persistent spirit of disobedience.