Many fail to distinguish between the condemnation in Adam, resulting in the condition of sheol/hades, and the condemnation of the second death, represented by the "Lake of Fire." Some believe that Jesus' sacrificial death for sin also includes those who are condemned to the "second death." (Or they fail to recognize the second death as being a second condemnation.) While Jesus' sacrifice does indeed save everyone who is dying in Adam from that death in Adam, we do not agree, however, that anyone is rescued from the "second death", except that in the sense that one may be rescued from coming under the condemnation of the second death. That is, one can be taking steps that could lead to the condemnation of the second death, and be rescued from taking to those steps before actually receiving the condemnation of the second death. Jesus' sacrifice, however, does not cover anyone who has actually become under the condemnation of the second death. Once one is given the additional sentence of the second death, there is no sacrifice for such. -- Hebrews 10:26.
One needs to realize that mankind in general is not under the condemnation of the second death. The condemnation upon man through Adam is the death in Adam (1 Corinthians 15:21,22; Romans 5:15-19). This condemnation was not eternal roasting in a place of fiery torture, nor was it what some like call "spiritual death," but it is a condemnation that resulted in physical death. Jesus is not roasting or suffering for eternity to pay the price for sin; he is not now suffering an eternal spiritual death; rather he physically died for our sins. (1 Corinthians 15:3) Thus, the wages of sin is physical death, and the benefits of that ransom applied is regarding human life. It was human life that was lost, and it is human life that is rescued. (1 Corinthians 15:21,22) It was from the death in Adam, which death results in the oblivious condition of hades/sheol (Ecclesiastes 9:5), that Jesus physically died to rescue mankind from. (1 Corinthians 15:21,22; Romans 5:6,8,15-19) It is from death and hades, not the second death, that mankind is rescued from. -- Hosea 13:14; Revelation 20:13.
No human can come under the condemnation of the second death, except that he first be "made alive" from the death in Adam. The overall application of the ransom sacrifice of Jesus belongs, not in this age, but the age to come, in the regeneration (Matthew 19:28), when the whole world will be made alive in the resurrection day. --John 5:28,29; 6:39,40,44,54; 11:24; John 12:47,48; Acts 24:15.
The world in general will be brought back to life in the last day here on earth for the final judgment. (John 12:47,48; Isaiah 2:2-4) Jehovah comes to judge the people on the physical earth by means of Jesus. -- Psalm 96:13; 98:9; Acts 17:31.
However, one can be reckoned -- counted -- as justified and made alive in this age through faith in the blood of Jesus, accounting the powers of the age to come as already upon him. -- Romans 3:21,22,24; 4:5,17,24,25; 6:11,13; Ephesians 2:1,5; Colossians 2:13; Hebrews 6:5.
Nevertheless, in this age, even one who has not been counted as alive by faith will be made alive in the age to come, and what he does in this age can affect his ability to escape from coming under the judgment of Gehenna (the second death) in the age to come. -- Matthew 5:22; 10:15; 11:22,24; 12:32; Mark 6:11; Luke 10:12,14; 12:10.
The Christian believer, however, in this age, until he has overcome, until he has put on incorruption (1 Corinthians 15:54), until he has attained the goal of perfection of faith and love (Philippians 3:12.14; Colossians 1:28; 4:12; 1 Thessalonians 3:10; Hebrews 6:1; James 1:4; 2 Peter 1:4-19; 1 John 4:17), is in danger of being harmed by the second death (Revelation 2:11) if he turns to willful sin, since there is no more sacrifice for sin. -- Hebrews 6:4-6; 10:18,26,27,29.
Thus, once one comes under the condemnation of the second death, there is no more hope for such. They are without life forever. There is no more sacrifice for sin, and the ransom sacrifice of Jesus does not cover those under that condemnation.
In the age to come, the unbelievers will be released from hades, because Christ went to hades, paying the wages of sin, so that all in hades may be released. These will be raised in the resurrection of judgment. (John 5:28,29; 12:47,48; Revelation 20:13) They are released from the condemnation in Adam by means of Jesus' sacrifice. They are not judged again to receive their former condemnation, but are judged by means of the things that are written in the books that are opened to them at that time, according to their works. (Isaiah 2:2-4; Daniel 7:10; Revelation 20:12) Those who fail to put on incorruption at that time (1 Corinthians 15:54) will come under a new condemnation, that is, the second death. No, they are never rescued from that condemnation, since there is no more offering for sin. They are devoured in the second death. (Revelation 20:9; Hebrews 10:27) It is then that the prophecy will come true: "The wicked will be no more. Yes, though you look for his place, he isn't there." -- Psalm 37:10.
See the study:
Mankind's Course to the Day of Judgment
Mankind's Course to the Day of Judgment
On the other hand, after the judgment day, the sheep will inherit the kingdom, the peaceful dominion, that was prepared for mankind from the foundation of the world (Genesis 1:26,28; Psalm 8:5-8; Matthew 25:34; Hebrews 2:6-8), as it was meant for mankind, incorruptible physical life on the earth, and they will live forever in peace upon the earth. -- Psalm 37:11,20; Isaiah 11:6-9; 25:8 (1 Corinthians 15:54); Matthew 5:5; 25:46; Revelation 20:1-4.
Revelation 20:14 - Death and Hades were thrown into the lake of fire. This is the second death, the lake of fire.
Revelation 20:15 - If anyone was not found written in the book of life, he was cast into the lake of fire.
Some have claimed this is not speaking of the person as being thrown into the lake of fire, but rather than it is sin and evil that thrown into the lake of fire. Thus they claim that absolutely everyone will live for eternity, and no one will be eternally destroyed.
While the book of Revelation is symbolic, what is actually stated does not warrant such a conclusion. The scripture does not say that it is simply sin and evil that is thrown into the lake of fire. One has to come up with a lot beyond what is written to force such an idea into what is stated. It is speaking of those, who after having receiving the knowledge of the truth, then willfully join forces with Satan against God and His Son. The fact that the new creature, before having overcome in having developed perfection of faith, can be harmed by the second death (Revelation 2:11) shows that it is speaking of persons, nor just principles of sin and evil.