When Peter confessed the revelation he received from the Father, that Jesus is the Christ, the Messiah, the Son of the Living God, our Lord Jesus said to him,
Blessed are you, Simon son of Jonah, for this was not revealed to you by flesh and blood, but by my Father in heaven. And I tell you that you are Peter, and on this rock I will build my church, and the gates of Hades will not overcome it. (Matthew 16:17-18)
Hades is the realm of the dead. Older English versions have often translated the Greek word ᾅδης as “hell.” Newer versions have begun to simply transliterate it as Hades. It is not to be confused with another word, Gehenna, found in the Greek New Testament and which also gets translated as “hell.” Gehenna refers to a geographical location and a temporal, historical judgment, and not some other-worldly, post-mortem experience.
Our Lord declared that he would build his Church and that the “gates of Hades” would not prevent it or prevail against it. In other words, not even death could stop it.
This is the Resurrection! It is Christ trampling down death by his own death on the Cross. The gates of Hades lay broken beneath his feet. The “strong man” has been bound, and Christ has plundered his house (Mark 3:27). The broken remnants of the chains and locks of death lay scattered about. Christ has taken the keys of Hades and death and has emptied them out (Revelation 1:18). He has taken Adam and Eve by the hand and brought them out to life — and with them, all who are in them!
Since the children have flesh and blood, he too shared in their humanity so that by his death he might break the power of him who holds the power of death — that is, the devil — and free those who all their lives were held in slavery by their fear of death. (Hebrews 2:14-15)
For just as in Adam all die, so also in Christ all will be made alive. (1 Corinthians 15:22)
As St. John Chrysostom said, in his Homily on the Cemetery and the Cross, “Christ, by his death bound the chief of robbers and the jailer, that is, the devil and death; and transferred his treasures, that is, the entire human race, to the royal treasury.”
And so is Christ building His Church. Through the Incarnation, the union of divinity with humanity, of God with humankind, the death of Christ on the Cross is the death of all humankind, so that the Resurrection of Christ from the dead might be the resurrection of all humankind.
In his Treatise on 1 Corinthians 15:28, St. Gregory of Nyssa said, “Now the body of Christ, as I often have said, is the whole of humanity.” Fr. John Behr extends this to its logical conclusion: “The Church is the whole of Creation seen eschatologically; from which we already see islands in the present.”
This is the Good News of the Gospel: Christ has broken the gates of “hell” — of death and Hades — and is building His Church.