A careful study of the Holy Scriptures gives a strong indication and makes it evident that an underworld, a world of spirit beings, exists. There can be no doubt about it. This underworld is the place to which sinners upon death, fallen angels, and unclean spirits or demons, depart. The part of the underworld to which sinners depart upon death is called the realm of the dead (Hades in Greek). This is a specific place, locality or abode to which is referred to as the heart of the earth (Lukas 16:23; Philip. 2:10).
That part of the underworld to which some of the fallen angels have been banned is known as Tartarus (2 Pet. 2:4) and serves as a place of confinement for those fallen angels that
await eternal punishment in the pool of fire which is hell itself (Matt. 25:41).
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