the realm of the dead: where everyone goes when they die, pictured as a temporary holding place until the resurrection
Hades is a Greek word the Jewish translators of the Old Testament picked up to render the Hebrew Sheol, the place all the dead go down to. They drained off most of its old pagan baggage (it was once the name of a Greek god of the underworld) and used it for the plain biblical idea: the shadowy realm where the dead are, parallel to the grave and to bodily decay. So when the New Testament uses it, the starting point is not the fiery hell of later imagination but Sheol, the holding place of the dead.
The shading shifts with the setting. Sometimes it is just rhetorical depth, the lowest point opposite the height of heaven (Jesus says proud Capernaum will be "brought down to Hades"). Sometimes it is the grip or power of death itself, as in "the gates of Hades." In Peter's Pentecost sermon it is the realm of the dead and decay that Christ truly entered but was not left in. In Jesus' story of the rich man and Lazarus it has compartments, one of comfort and one of torment, reflecting the Jewish picture of the time. In Revelation it is even personified, a hostile power that follows Death around and is finally thrown into the lake of fire.
These are not separate words with separate meanings; they are the same realm of the dead seen from different angles. The one consistent thread, especially clear in Revelation, is that Hades is a temporary custodian. It holds the dead for a time, then has to give them back at the resurrection, and is itself destroyed at the end. That is what keeps it distinct from the final place of judgment.
Nuances
Whether "the gates of Hades" pictures the imprisoning power of death (the church will not be held by death) or hostile underworld powers attacking the church.
- contestedA metaphor for death and its imprisoning power: death will not be able to hold the church.; R. T. France, The Gospel of Matthew (NICNT; Eerdmans, 2007), 622-623; J. P. Lewis, "'The Gates of Hell Shall Not Prevail Against It' (Matt 16:18)," JETS 38/3 (1995): 349-367
- contestedThe ungodly powers of the underworld which will assail the church.; W. D. Davies and Dale C. Allison Jr., Matthew (ICC; T&T Clark, 1991), 2.631-633; Joel Marcus, "The Gates of Hades and the Keys of the Kingdom (Matt 16:18-19)," CBQ 50 (1988): 443-455
Whether the parable's picture of Hades with a compartment of torment teaches doctrine about the intermediate state, or merely borrows familiar Jewish and folkloric afterlife imagery to make an ethical point.
- contestedThe parable borrows widely-attested imagery and is not teaching about the afterlife; its point is the sufficiency of Moses and the prophets.; Joachim Jeremias, The Parables of Jesus (rev. ed., 1972), 185-186; N. T. Wright, Jesus and the Victory of God (Fortress, 1996), 255
- contestedThe scene depicts the morally divided intermediate state of Hades on the model of 1 Enoch 22, with the dead awaiting final judgment.; Darrell L. Bock, Luke (BECNT; Baker); Richard Bauckham, "The Rich Man and Lazarus," NTS 37 (1991): 225-246