Hades, originally the Greek god of the underworld, is the namesake for the place where departed spirits live. It was frequently used in the Bible as a synonym for hell or the grave (Psalm 9:17; 55:15; 116:3).
As Jesus used it in Matthew 16:18, Hades seems to refer to the powers of evil that resisted Jesus, including Satan's ultimate weapon of physical death. Jesus told his disciples that they would have to confront the "gates of Hades" (Matthew 16:13-20) which probably referred to the powers of hell and Satan arrayed against God.
Jesus' words also carried symbolic meaning because they were spoken in Caesarea Philippi, a pagan city that was filled with moral corruption. Pagans believed that water symbolized the abyss and that caves were a door to the underworld. Because Caesarea Philippi stood near a cave with spring water flowing from it, the pagans naturally thought of the cave as a gate to the underworld.
As he challenged his disciples to confront the "gates of Hades," Jesus stood near this cave, the physical picture of the gates of hell. Caesarea Philippi represented the worst evils of culture; it was filled with idols, shrines, and immoral worship practices.
Yet Jesus assured his disciples that the "gates of Hades" would not be able to stand against the power of God's people. Jesus defeated Satan through his suffering, death, and resurrection. Therefore his people could overcome Satan and transform evil places like Caesarea Philippi.
Today, God's people must continue to confront the "gates of hell" in our culture, those places that are dominated by evil. Relying on God's power, we can face these fearful circumstances and overcome the forces of Satan that we encounter every day.