I would say that whether or not Jesus did is an open hand issue, which is thus not crucial for one’s salvation. But whether Jesus did or not, his excruciating agony (which was immeasurably worse than the physical torture of the crucifixion) of being separated from the Father even for a moment, was the very worst possible hell Jesus could have personally experienced, so that I and all of us undeserving sinners may be reunited with the Father

In both the passage in ephesians and 1 Peter, the passage says the complete opposite of John Piper’s interpretation and there are at least 3 other passages in the new testament that speak against his interpretation. For instance, Jesus likens himself to Jonah who “spent three days and three nights in the belly of the whale” Interesting, Jonah himself writes, “I went down into the countries underneath the earth, to the peoples of the past…but you lifted my life from the pit, O Lord, my God.”  

Also, he did not  address  the Jesus told Mary on the third day that he had not ascended to the Father. Instead, he used the thief on the cross passage to justify his particular interpretation.

So I feel unconvinced by his interpretation because
#1 The Apostles creed has that passage  
#2 There are 5 other biblical passages that say Jesus went to hades (corroboration)
#3 Jesus told Mary he had not yet ascended on the third day
#4 The thief on the cross passage could easily mean “I tell you today, …”
#5 John Piper is a calvinist

I am only kidding about #5. =)
But I still maintain #1, #2, #3, and #4. I think they present a VERY strong case against John Pipers interpretation and hence, reasonably show that Jesus probably did go into hades. What exactly he was doing there, where hades is and who did he rescue is a different question which I think we can only speculate on.    

I am a bit surprise that  John Piper would rather avoid  reciting  that part of the apostles creed than to embrace the mystery that Joe pointed out.  

I personally feel more  unconformable saying that Jesus was  separated  from the Father. That creates several theological “uncomfertableness” for me considering the nature of the trinity.

The story of the Rich man and Lazarus makes sense because when Jesus narrated this, the two sides still coexisted. However, at the martyrdom of Stephen (post-resurrection), Stephen saw Jesus in heaven standing at the right hand of God, and he directly prayed to Jesus to receive his spirit. That he prayed Jesus to receive his spirit in heaven I think needs no explanation. So, for me to recite “He descended into Hades” makes better sense and helps me love Jesus more.

St. Augustine: Christ preached to the ancient world through the person of Noah, urging the wicked to repent before the floodwaters of judgment

St. Robert Bellamine: Christ descended to the dead to announce his salvation to those sinners who had privately repented just before the onset of the flood.  

A Modern Interpretation: During Christ Ascension into glory, he presented himself as victor and conquered to a company of demons imprisoned in the lower heavens.  

There are also more specific interpretations to who the people are that Jesus preaches to:

Some say it is the souls of the wicked during the time of the flood. But this is a strange interpretation since it is unclear why Jesus should single out these particular people. Why not the people of Sodom and Gomorrah? We also have no biblical source to suggest that these people repented.  In fact, they are used as an example of a  generation  that is condemned by God.  

One method for gaining clarity involves looking towards non biblical  sources  which were  commonly  references during the apostles times (e.g., Jubilees, 1 and 2 Enoch). For instance, in Genesis we are told about the “sons of God: which several jewish text identify as rebellious angels who corrupted the world of men before the flood. Being spirits, they could not be destroyed by the waters of the flood so the Lord thrust them into prisons in the underworld.  

Under this account, these people who Jesus preaches to are fallen angels which messhes much better with the use of the word spirits as angels in the new testament (e.g., Matthew 12:45, Luke 10:20, Hebrew 1:14). However, I personally have trouble with this interpretation since Angels are fully aware of Gods glory which presents a problem for me to see how they could be saved after rejecting God.  

So in summary, several possibilities seem likely:
#1 He saved the righteous from the times before Christ (sheol)
#2 He saved the righteous and those who repented during the flood  and other disasters
#3 He saved some of the fallen angels
#4 He saved the righteous people and the fallen angels before the time of Christ.  

I am personally inclined towards possibility #2. And I am more inclined towards believing he freed these souls from this above of the dead and not from hell. Of course, this is all theological speculation but I think possibility #2 is best supported by scripture. Almost all the scriptural references to him descending into hell are translations from the word hades which is better translated as the underworld and not hell.  

This whole topic is tricky since there are many orthodox theologians who support one of the four mentioned possibilities. The Catechism has an interesting paragraph on this topic:

635 Christ went down into the depths of death so that “the dead will hear the voice of the Son of God, and those who hear will live.” Jesus, “the Author of life”, by dying destroyed “him who has the power of death, that is, the devil, and [delivered] all those who through fear of death were subject to lifelong bondage.” Henceforth the risen Christ holds “the keys of Death and Hades”, so that “at the name of Jesus every knee should bow, in heaven and on earth and under the earth.”. . . He has gone to search for Adam, our first father, as for a lost sheep. Greatly desiring to visit those who live in darkness and in the shadow of death, he has gone to free from sorrow Adam in his bonds and Eve, captive with him – He who is both their God and the son of Eve. . . “I am your God, who for your sake have become your son. . . I order you, O sleeper, to awake. I did not create you to be a prisoner in hell. Rise from the dead, for I am the life of the dead.”
I would curious to hear how people reconcile the many passages that allude to Jesus going to hades with the passage of the thief on the cross. As I have stated before, the passage could easily be translated to mean: “Truly I tell you today, you will be with me in paradise.” In the Purgatory thread, the only person who responded to my statement was David who said:

“Jesus says the phrase “I tell you the truth” with some promise after that  phrase  78 times in the New Testament. he never says “I tell you the truth today” with the word “today” appearing as a part of that common phrase that  he uses.”
Although I find this to be a wise observation, it does not really support his argument very strongly. Just because Jesus never previously used the word “today” with the phrase “I tell you the truth” doesn’t mean he could not have meant “I tell you the truth today, you will…” After all, by David’s own admission, Jesus never uses those two phrases together. Hence, it seems perfectly reasonable to assume that he could have used it to say, “I tell you the truth today,…” and the topic of this thread, further supports this. After all, we are told Jesus descended into the abode of the dead. And when Mary first saw him on the third day, he told her not to touch him since he had not yet ascended to the father. So I think this presents three key pieces of evidence to strongly support the assertion that Jesus said, “I tell you the truth today, …” and not, “I tell you the truth, today…”  I would love to hear a charitable  rebuttal  to this from David or anyone else.

I really like the conclusion of the article. I think mystery is the healthiest approach to take towards this topic. We really don’t know. I wish people would not respond to mystery by ignoring that line on the apostles creed. But I can understand that attitude. After all, mystery can sometimes cause a lot of discomfort that we do not understand the full workings of the gospel. But we should be okay with that because we are called to have faith and not to posses all knowledge.