Hades and The Sea

I've become a believer in Universal Salvation, and I stress the importance of a Physical Bodily Resurrection.  However I remain undecided on whether or not I think the Soul/Spirit has a concise state between physical Death and Resurrection, i.e. on the issue of Soul Sleep.  No matter what I would say I don't believe in the Platonic notion of the Immortality of the Soul because I don't believe souls have a Pre-Existence.

Those topics bring up discussion of the words translated "Hell" a lot.  Sheol and Hades (which are clearly the Hebrew and Greek counterparts to each other) are sometimes translated Grave, insinuating they can sometimes be an idiom for being buried in the Earth rather then an Underworld where disembodied Souls and/or Spirits reside.  For example the KJV translates Sheol that way a lot, including the first few times it shows up in Genesis, but translates Hades this way only once, in 1 Corinthians 15:55 which is also the only time Paul ever uses the word.

I had been highly skeptical of that ever being a valid translation, especially since there are other words for Graves, Tombs and Sepulchers.  But then I noticed something in Revelation chapter 20 I hadn't before, in verse 13.

"And the sea gave up the dead which were in it; and death and hell delivered up the dead which were in them:"

The reference to there being dead in the sea here clearly refers to how many people are buried at sea, in ancient and medieval times when we didn't have modern preservation technology if you died while at sea you were probably buried at sea whether you would have preferred that or not because the body was going to start to rot.

So that heavily implies "hell" here (which is Hades in the Greek) being used in contrast to that is the location of physical bodies not otherworldly souls/spirits.

"But Death is also a location name then" you may ask.  The Psalms speak often of the Valley of the Shadow of Death which I feel is a term for Sheol whether it's used literally geographically or poetically.

This also makes me start wondering about the Beast rising out of the Sea in chapter 13 (it is the same word for sea in the Greek).  Since there is already reason to suspect the beast is subject to an early Second Resurrection, maybe this is an idiom of that.  But I can't right now think of any historical Antichrist candidates who were buried at sea.

This verse certainly further shows that the Resurrection isn't merely Spiritual.