In Revelation 1:18 Jesus says, “I am the Living One; I was dead, and now look, I am alive for ever and ever! And I hold the keys of death and Hades.” Possessing the “keys of death” means that the risen Christ has control and authority over death. In John 10:17–18, Jesus says, “The reason my Father loves me is that I lay down my life—only to take it up again. No one takes it from me, but I lay it down of my own accord. I have authority to lay it down and authority to take it up again. This command I received from my Father.” When Jesus died, He died according to His own timing, when He “gave up his spirit” (John 19:30). Pilate was surprised to hear that Jesus was already dead (Mark 15:44). Jesus, who has the authority over death, had the unique power to give up His spirit and to rise from the dead. Moreover, He has the authority to release His followers from death in order that they may be with Him forever.
Think of the concept of giving someone “the key to the city.” This key is sometimes a large, cartoonish key that fits no lock but is symbolic of an honor bestowed. Someone given “a key to the city” is considered welcome and honored within that city. The Bible frequently speaks of keys as representing control or authority over something or someone. This concept makes sense; to possess a master key to a building is to have the authority to open any of its doors and enter any room.
Isaiah 37:2 speaks of Eliakim, the son of Hilkiah, an honorable man sent on an important errand. In chapter 22, it was written that Eliakim would be given authority and that God would “place on his shoulder the key to the house of David.” By the “key to the house of David,” it is meant that the Lord would place Eliakim in a position of authority. Later, Eliakim becomes the governor of the palace in Jerusalem.
In Revelation 9:1–2, an angel is given a key to, or control over, the bottomless pit, and he uses the key to open that pit. Later, an angel is seen locking things in the bottomless pit (20:1–3).
Eternal life through Jesus Christ is the blessed assurance John describes in 1 John 5:6–13. Jesus having the keys of death means He has the power to release from death those who receive the gift of salvation He offers.