Jesus announced in Nazareth, very early in His ministry, that “The Spirit of the Lord is on me, because he has anointed me to preach good news to the poor. He has sent me to proclaim release to the captives and recovery of sight to the blind, to set free the oppressed” (Luke 4:18 CSV).
Here's another example of dual meanings in the Bible for "release” refers to both physical release from bondage and imprisonment as well as release from the penalty of sin: forgiveness and pardon.
We are told that Jesus freed “those who all their lives were held in slavery by their fear of death” (Heb 2:15 NIV), and He did this by becoming sin and taking the punishment for our sin on Himself. We no longer have to fear death and the consequences for sin because Jesus shared His reward for His sinlessness with us and at the same time Jesus took our punishment completely away from us for our sin. He gave His life as a ransom for many (Matt. 20:28).
But how did Jesus physically release the captives?
Before the resurrection of Jesus, dead saints had no access to heaven since they were bound by the law of sin and death but the psalmist foretold that when Jesus “ascended on high; (He would lead) captives away” (Psa. 68:18).
This is literally what happened. When Jesus died, the earth shook, rocks split and gravestones rolled away and dead saints were resurrected (Matt. 27:51-53). For 3 days long dead saints wandered around Jerusalem until Jesus was resurrected. This resurrection of dead saints was foretold in Isaiah 26:19: “Your dead shall live; together with my dead body they shall arise. Awake and sing, you who dwell in dust; for your dew is like the dew of herbs, and the earth shall cast out the dead.” Actually, the Septuagint adds that Job was resurrected with the ones that the Lord raised up (Job 42:17).
When Jesus appeared to Mary Magdalene in the garden after His resurrection, He asked her not to restrain Him because He had to first ascend to His Father (John 20:17)---to present the liberated captives to His Father before He returned to the earth. The scripture informs us that "When he went up to the very heights, he took many captives with him; he gave gifts to people" (Eph. 4:8 GNT).
Paul acknowledged that in Christ we now go directly to be with the Lord at our death. “I am hard pressed between the two. My desire is to depart and be with Christ, for that is far better. But to remain in the flesh is more necessary on your account” (Phil. 1:23-24 ESV).
As Christians we have a sure and firm assurance that we will be forever with the Lord: that He will never leave us or forsake us. In fact, this is the reason why Jesus told Martha that if we believe on Him we will never die (John 11:26).