How do Baptists interpret Revelation 20 and 21? I understand that Revelation is one of the more challenging books to ask about, but what I hope to find out is what Baptists believe chapters 21 and 22 foretell for the future.  


Chapter 20:1-3 and 20:7-9; do they believe the confining of Satan to
the abyss and then release onto the earth is literal or figurative?
What do they derive from the verses about a “new earth” described in
Revelation 21:1-4?
Just to let you know, I haven’t had as much fun as this since lockdown started.  After hours of research, I’ve discovered lots of really useful information on General Baptists, Particular Baptists and Reformed Baptists.  I’ve delved into the London Baptist Confession of Faith (1689), the Westminster Confession of Faith and Calvin’s ‘Institutes.’  It has been a fascinating but futile journey because it turns out that Baptists throughout the world are split on the subject of eschatology.
From what I’ve read, it seems Charles Spurgeon was a premillennialist, English Reformed Baptists appear to be amillennialist whereas American Reformed Baptists are split 50/50 between historic premillennialist and amillennialist.
The only honest answer I can give is that Baptist eschatology can be summed up by saying Jesus Christ will return personally and visibly in glory to the earth; the dead will be raised; and Christ will judge everyone in righteousness.
As to how Baptists interpret Revelation, the jury is still out.  One thing is clear, though, and that is that Reformed and Particular Baptists follow in the theological footsteps of John Calvin, especially with regard to the doctrine of salvation. Here is one useful quote taken from his ‘Institutes’:

Book 3, Chapter 25, Section 6 – Condition and abode of souls from death till last day: It is foolish and rash to inquire into hidden things, farther than God permits us to know. Scripture, after telling that Christ is present with them, and receives them into paradise (John 12:32), and that they are comforted, while the souls of the reprobate suffer the torments which they have merited, goes no farther. What teacher or doctor will reveal to us what God has concealed? As to the place of abode, the question is not less futile and inept, since we know that the dimension of the soul is not the same as that of the body.  When the abode of blessed spirits is designated as the bosom of Abraham, it is plain that, on quitting this pilgrimage, they are received by the common father of the faithful, who imparts to them the fruit of his faith.
Still, since Scripture uniformly enjoins us to look with expectation to the advent of Christ, and delays the crown of glory till that period, let us be contented with the limits divinely prescribed to us--viz. that the souls of the righteous, after their warfare is ended, obtain blessed rest where in joy they wait for the fruition of promised glory, and that thus the final result is suspended till Christ the Redeemer appear. There can be no doubt that the reprobate have the same doom as that which Jude assigns to the devils, they are &quot;reserved in everlasting chains under darkness unto the judgment of the great day,&quot; (Jude ver. 6).
Book 3, Chapter 25, Section 12 – Happiness of Elect – Misery of Reprobate: Moreover, as language cannot describe the severity of the divine vengeance on the reprobate, their pains and torments are figured to us by corporeal things, such as darkness, wailing and gnashing of teeth, inextinguishable fire, the ever-gnawing worm (Mt. 8:12; 22:13; Mark 9:43; Isa. 66:24).
As we thus require to be assisted to conceive the miserable doom of the reprobate, so the consideration on which we ought chiefly to dwell is the fearful consequence of being estranged from all fellowship with God, and not only so, but of feeling that his majesty is adverse to us, while we cannot possibly escape from it. For, first, his indignation is like a raging fire, by whose touch all things are devoured and annihilated. Next, all the creatures are the instruments of his judgment, so that those to whom the Lord will thus publicly manifest his anger will feel that heaven, and earth, and sea, all beings, animate and inanimate, are, as it were, inflamed with dire indignation against them, and armed for their destruction. Wherefore, the Apostle made no trivial declaration, when he said that unbelievers shall be &quot;punished with everlasting destruction from the presence of the Lord, and from the glory of his power,&quot; (2 Thess. 1:9) Source: https://reformed.org/master/index.html?mainframe=/books/institutes/books/indxbk3.html

During the first five years of my Christian life, I was a member of an English Baptist Church.  I can't recall the senior minister ever delivering a sermon on eschatology. I put that down to the fact that he was more concerned with preaching the gospel and making sure we had a firm grasp on the important doctrines to do with sin, salvation and the person of Christ Jesus.  Heaven and hell were taught as realities as was the second coming.  Dispensationalism and Millennialism were not subjects for Sunday sermons, although the senior minister had plenty books on the subject.  Had I been curious enough to enquire, I dare say he would have been willing to introduce me to those subjects.
Suffice to allow Calvin to have the last word: “It is foolish and rash to inquire into hidden things, farther than God permits us to know.”