1:18 the living One; and I was dead, and behold, I am alive forevermore, and I have the keys of death and of Hades.
the LIVING ONE;
Christ, in using this expression, indicates He is the same as the LIVING God.
Who is the LIVING GOD?
It is this LIVING GOD who is speaking here!
and I was dead, and behold, I AM ALIVE FOREVERMORE, and
This expression parallels the `first and last' idea of the previous verse, but here it specifically refers to Christ the Messiah. It was He who died on the cross and rose again to be ALIVE FOREVERMORE.
This becomes a central theme throughout the Revelation. See how many times the words "blood" and "Lamb" are used. This is fundamental to our living forevermore too. We have been bought with a price - 1 Corinthians 6:20 and we have the hope of glory because He was raised from the dead - 1 Peter 1:18-20.
Paul clearly explains that Christ's death was a onetime event. He doesn't have to die annually to make atonement for sins like the High Priests of Old Testament times made atonement - Hebrews 9:23-28.
I have the keys of death and Hades.
Whoever has the keys to anything controls access to and from the area. Here Christ says He has the keys to both death, our end of the physical body, and Hades, the destiny of our souls. Hades of the New Testament is the same as Sheol of the Old Testament.
They refer to "the nether region" or, as some say, the center of the earth. During the time that Christ was "dead" physically, Ephesians 4:7-10 says he descended into the lower parts of the earth. But God would not abandon Him there according to the prophesy given in Psalm 16:10, but He ascended from there leading the ones who were held captive up to His high mountain - Psalm 68:18.
So what is this place, Hades? It is located in the heart of the earth - Matthew 12:40 and Numbers 16:30-33. It is divided into two compartments or areas separated by a large gulf - Luke 16:19-31. One compartment is for non believing departed souls and the other for believing or righteous souls to rest.
There are gates or doors to these two compartments. Formerly, the keys to the gates were in satan's hand (Hebrews 2:14 and Matthew 16:18). But Christ when he descended into Hades took the keys away from satan - Acts 2:22-24; He conquered death (Romans 6:9) forever and when we now die, as believers, we are with Him (Philippians 1:23).