Hi Ravi and Tina,
I wouldn't say I'm more knowledgeable. This question happened to be partly covered under the
4 Questions thread started by Satish, though. Here is a relevant passage (1 Peter 3:19):
17 For it is better to suffer for doing good, if suffering should be God's will, than to suffer for doing evil. 18 For Christ also suffered for sins once for all, the righteous for the unrighteous, in order to bring you to God. He was put to death in the flesh, but made alive in the spirit, 19 in which also he went and made a proclamation to the spirits in prison, 20 who in former times did not obey, when God waited patiently in the days of Noah, during the building of the ark, in which a few, that is, eight persons, were saved through water.
Here is the quote from Rev Eric regarding this:
Heaven and hell are the desitinations for those who have been judged according to their acceptance or rejection of the salvation provided for them by Christ. The question remains, however, what happened to those who died before Jesus' death on the cross won that salvation for all humankind?
The ancients believed that all the dead went to limbo. Those who lived evil lives were in the lower level of limbo and the righteous lived on the higher level. The parable of Lazarus the Beggar (Lk 16:20 & ff.) seems to contain an illustration of this concept.
After Jesus died on the cross, he descended to the dead (i.e., those in limbo) in order for them to know Him and be given the opportunity to accept or reject His salvation. Those who accepted it went to heaven and those who rejected it went to hell. So it is at this time that the doors of heaven and hell were opened for all humankind, and that limbo was emptied and, presumbably, never used again (or at least not this particular incarnation of limbo as a kind of waiting room).
Hope this helps. If not, let me know.