IF "redemption" is the answer to "death,"
THEN we might gain some insight into the meaning of "redemption" by reviewing some facts about "death."
FACT: God warned Adam that he would "die" the "day" he ate from the Tree of Knowledge of Good & Evil. "Day" had already been defined in this context by saying "there was evening and there was morning, the sixth day," etc., (Gen 1:31), the period between "evening&mornings" in which Adam was made. Since God cannot lie, (Heb 6:18), Adam "died" that very day, (no poetic or prophetic or figurative license taken). And yet, Adam's biological body remained animated until he "died" (same exact word whether Hebrew or Greek Text), 930 years later, Gen 5:5, when Adam's biological, natural body ceased to be animated. Adam "died" 2 times: Adam "died" the very day he ate the fruit per Gen 2:17 AND Adam "died" 930 years later, as well per Gen 5:5 : "died" is the same exact word in both cases, (whether Hebrew MT or LXX Greek Old Testament texts). Add to this the entirety of the Biblical record of uses of the word "died." (There is a very powerful reason why God kept Adam from eating from the Tree of Life after Adam's inner-man died that day he ate the forbidden fruit of the Tree of Knowledge of Good & Evil, Gen 3:22-24).
Evidently, Bible teaches that there are 2 distinct dimensions to "death," (Mat 10:28, Rev 2:11, Rev 20:6, Rev 20:14-15):
1) "Death" when the inner-man "dies" when separated from intimate fellowship with Life, ie, God Himself.
2) "Death" when the outer-man, his biological, mortal-natural body, "dies" when separated from its animating spirit, James 2:26.
God's answer to this "Death" with 2 distinct dimensions.
must be a "Redemption" with 2 distinct dimensions.
2 Distinct Dimensions of Redemption:
1) Redemption of the inner-man, his spirit via being Born-Again, John 3:16, Col 2:12-13 & Col 3:1.
2) Redemption of the outer-man, his body via the Resurrection of the Just that all the New Testament writers eagerly anticipated with Christ's Return per encouraging promises in passages such as 2 Tim 2:11-18, Philippians 3:10-13, Rev 20:4-5, Rom 8:11, Rom 8:23, 1 Thess 4:13-18 to 1 Thess 5:1-2, 1 Cor 15:21-23, 1 Cor 15:42-53, and 2 Cor 4:14. But woe to the soul whose body is resurrected while his spirit remains dead, separated from covenant-fellowship with God. Such is the fate of "the rest of the dead” who come to life after the 1000 years are completed in Rev 20:4-6, Rev 20:11-15. There is a very powerful reason why God kept Adam from eating from the Tree of Life after Adam's inner-man died that day he ate the forbidden fruit of the Tree of Knowledge of Good & Evil (Gen 3:22-24) and it wasn't to keep Adam from being born again. It was to keep Adam's outer-man (body) from living forever while his inner-man remained dead. God wanted to bring about the redemption of Adam's inner-man BEFORE granting him redemption of his body, immortality in a spiritual body, a spiritual body that would be glorified at judgment rather than condemned.
Whosoever obtains redemption, rebirth, of the inner-man via being Born Again in obedience to John 3:7 obtains one dimension of the "Everlasting Life" of John 3:16 immediately: his inner-man, his soul is saved, redeemed from destruction, Matt 10:28. When such an individual's outer-man, his biological, mortal-natural body, goes on to physically die and decompose, the Christian is biblically described as being not "dead" but "asleep" (1 Cor 15:16, 1 The 4:13-15, 2 Pet 3:4). For the dead in Christ, his outer-man is dead, (ceases to be animated), but his inner-man remains very much alive. So sure is this promise within that remains alive, this promise that the outer-man, the body will be redeemed,  be resurrected, come to life per Philippians 3:11-12 & Rev 20:4, that the experience is rightly described as "being asleep." One whose inner-man has been redeemed, reborn via the Born-Again experience, (the birth of his spirit per John 3:3-8), has a much more certain confidence that he will awake again to animate a body than the confidence he had that he would wake up each morning throughout his biological experience. The Christian has within him the promise that the 2nd Death will not affect him (Rev 2:11). Though he "sleeps," (death of his biological, mortal-natural body), this time, when he awakes, he awakes to animate a glorified, immortal-spiritual body (1 Cor 15:44), his old, biological, mortal-natural body being "exchanged in a twinkling of an eye" for his new, glorified, immortal-spiritual body (1 Cor 15:50-55). THIS is the redemption of the body, the resurrection-transformation-glorification that Paul looked forward to, Phillippians 3:1-13, 2 Tim 2:11-18, Rev 20:4-5, Rom 8:11, Rom 8:23, 1 Thess 4:13-18 to 1 Thess 5:1-2, 1 Cor 15:21-23, 1 Cor 15:42-53, and 2 Cor 4:14. Hallelujah! Glory to God through Jesus Christ, the Firstborn from the Dead who is now the Judge of the Living and the Dead! Hallelujah!
In brief, in the context of John 6:54
1) "Eternal Life" = redemption of one’s Inner-Man, i.e., Salvation of the soul.
2) "Raised Up at the Last Day" = redemption of one’s Outer-Man, his body, with a spiritual body, i.e., Resurrection from the dead.
"Whoso eatheth My Flesh, and drinketh My Blood, hath Eternal Life, and I will raise him up at the Last Day." ~ Jesus, around AD 28, (John 6:54)
"Do not be afraid of those who kill the body but cannot kill the soul. Rather, be afraid of the One who can destroy both soul and body in Hell." (Matthew 10:28)
Job 19:25-27
25 I know that my Redeemer lives,
and that in the end he will stand upon the earth.
26 And after my skin has been destroyed,
yet in my flesh I will see God;
27 I myself will see him
with my own eyes — I, and not another.
How my heart yearns within me!
It really is unwise
to confuse the two dimensions of "death"
as well as
to confuse the two dimensions of redemption in the increasingly awkward effort to force all fulfillment of Scripture by 70AD.
The 30-70AD Millennial view, that the Resurrection that Paul and the Apostles looked forward to (Phillippians 3:10-13) was the covenant life they already had via faith in Christ, is fatally flawed, (2 Tim 2:11-18). It leads directly to Universalism, the kind of preterist Universal Salvation that rallys around Max King aka “Comprehensive Grace” that goes "Beyond Salvation" as presented by Jesus and His Apostles in the New Testament record.
Let us remember that it was Hymenaeus & Philetus who were saying things like, "Since the first Resurrection, which is already past, was all about souls "coming to covenant life" in Christ (Rev 20:4), the Resurrection of the rest of the dead when the 1000 years ends (Rev 20:5) will be about the rest of the dead "coming to covenant life" in Christ, too: nobody but the Devil is going to Hell!" (2 Tim 2:11-18 Phillippians 3:10-13). This is how 30-70AD Millennialism's Gnostic-style "figurative-covenant resurrection" leads directly to Universalism. They hallucinate the term "covenant" into the text of Rev 20:4 and read it, "they came to covenant life" when speaking of the First Resurrection. The thing is, Rev 20:5 employs the same grammar and vocabulary to describe how "the rest of the dead" "come to life" a 1000 years later. If we insert "covenant" before "life" in Rev 20:4, then we must accept that "covenant" belongs before "life" in Rev 20:5, as well. That is, both the souls of Christ's mark-of-the-beast-rejecting martyrs and the souls of "the rest of the dead" eventually BOTH "come to covenant life" in Christ. THAT, inescapably, is Universalism.
Revelation 20:4-5 ~foreseen around 63AD by exiled Apostle John in the predictive vision about "things shortly to come to pass", Rev 1:1, Rev 4:1
And I foresaw the SOULS of those who had been beheaded because of the testimony of Jesus and because of the word of God, and those who had not worshiped the beast or his image, and had not received the mark upon their forehead and upon their hand; and they came to covenant life and reigned with Christ for a thousand years. 5 The rest of the dead did not come to covenant life until the thousand years were completed.
(NASB-with the term "covenant" hallucinated into the Text by 30-70AD Millennialism aka "Full" Preterism aka Covenant Eschatology)
The only way this passage can make sense without Universalism is to understand that the "Resurrection" process being described here by which both groups "come to life" CANNOT be talking about "coming to covenant life": it can only mean "Souls, whether of Christ's martyrs or the rest of the dead, came to animate bodies (to life)."
And this is love, that we walk after Christ's commandments ~2 John 6
REWARDS Delivered at the Fall of Babylon (AD70 Jerusalem)