In Latter Day Saints theology, the term spirit world refers to the realm where the spirits of the dead await the Resurrection. In LDS thought, this spirit world is divided into at least two conditions: Paradise and Spirit Prison:
Paradise includes "the spirits of the just, who had been faithful in the testimony of Jesus while they lived in mortality."
Spirit Prison is the condition of the spirits of "the wicked ... the ungodly and the unrepentant who had defiled themselves while in the flesh ... the rebellious who rejected the testimonies and the warnings of the ancient prophets...." The latter will continue to receive gospel teaching and be given the opportunity to repent, though their disposition toward repentance will only change as they recognize and accept gospel truths and believe in Jesus Christ.
The spirit world is believed to be a place of continued spiritual growth for all spirits who embrace the teachings of Christ. Christ himself organized this teaching process during the time between his death on the cross and his resurrection, among those who had been faithful to the gospel, so that they could teach those who had not yet heard its message.
Brigham Young stated,
"Where is the spirit world? It is right here...Do [spirits of the departed] go beyond the boundaries of the organized earth? No, they do not...Can you see it with your natural eyes? No. Can you see spirits in this room? No. Suppose the Lord should touch your eyes that you might see, could you then see the spirits? Yes, as plainly as you now see bodies."
Joseph Smith, Jr. taught:
"The spirits of the just...are not far from us, and know and understand our thoughts, feelings, and motions, and are often pained therewith." 
Spirit prison is believed by the Latter-day Saints to be both a place and the state of the soul between death and the resurrection, for people who have either not yet received knowledge of the gospel of Jesus Christ, or those who have been taught but have rejected it. It is a temporary state within the spirit world, and is sometimes referred to in the scriptures as hell. The suffering associated with the spirit prison refers to anguish of soul because of acute knowledge of one's own sins and unclean state.
Latter-day Saints believe that spirit prison (a name based on the phrase "the spirits in prison" in the KJV translation of Peter 3:19) is a place in the post-mortal spirit world for those who have "died in their sins, without a knowledge of the truth, or in transgression, having rejected the prophets". This is a temporary state in which spirits will be taught the Gospel and have the opportunity to repent and accept ordinances of salvation that are performed for them in temples. Those who accept the Gospel may dwell in paradise until the Resurrection. Those who choose not to repent but who are not sons of perdition will remain in spirit prison until the end of the Millennium, when they will be freed from hell and punishment and be resurrected to a telestial glory.
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