Gates of Hades or Hades Gate?

Where are the Gates of Hell?

Matthew 16:18
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.

This verse is often interpreted as if the gates of Hades could sprout legs, lift itself off its hinges and come over to the Kingdom of Heaven, banging on the door, trying to get at the Church inside. I disagree with that interpretation.

I think it should be interpreted as The Kingdom of Heaven having a "Hades Gate" that leads to Hades, as opposed to viewing Hades as a walled city with gates. This view would be similar to how ancient Jerusalem had the “Harsith Gate” (see Jeremiah 19:2) that led to the Valley of Hinnom (an area known as Gehennah).

With that understanding, Mathew 16:19 makes more sense:

I will give you the keys of the kingdom of heaven; whatever you bind on earth will be bound in heaven, and whatever you loose on earth will be loosed in heaven.

The “keys of the kingdom” are the keys to the gate – to let people into the kingdom. This concept parallels that of the imagery of other parts of Matthew such as the parable of the 10 virgins. The 5 foolish virgins were outside the door, trying to get in.

Matthew stresses the idea of not judging but bringing the sinner back through forgiveness (Matthew 6:12,14, 9:6, 18:21,35). And forgiveness is equated with "loosening":

Matthew 18:27
Then the lord of that servant was moved with compassion, and loosed him, and forgave him the debt.

This loosening refers to the “binding and loosening” in 16:19 (already quoted above) and also in 18:18.

I tell you the truth, whatever you bind on earth will be bound in heaven, and whatever you loose on earth will be loosed in heaven.

And we see similiar wording in John 20:23 but instead of binding/loosening, it speaks of forgiveness:

If you forgive anyone his sins, they are forgiven; if you do not forgive them, they are not forgiven.

Hades was understood to be the realm of the dead and those in the church were once dead but now are saved and brought into the Kingdom (through the gate).

Colossians 2:13 (similar to Ephesians 2:1)
When you were dead in your sins and in the uncircumcision of your sinful nature, God made you alive with Christ. He forgave us all our sins,

So the gates of Hades are not “attacking” the church but trying to “block” it from entering. But the gates of Hades will not prevail because of forgiveness of sins.