'The first resurrection,' mentioned in Revelation 20:5, 6, does not mean a first resurrection, but the essence and primary part of resurrection, which is salvation and eternal life. There is only one resurrection to life. A second does not happen, and is not mentioned anywhere in the Bible.

(References: Apocalypse Explained 6; Apocalypse Revealed 851; Revelation 20:5-6)

5057. I once saw a mortar, standing by which there was a man who had an instrument made of iron. In his delusion the man thought he was pounding human beings in the mortar, tormenting them dreadfully. He took great delight in what he was doing, and that delight was communicated to me to enable me to know the nature of it and how strong it was in people of his kind. It was a hellish delight, and angels told me that it was the kind that reigned among the descendants of Jacob. These never felt more delighted than when they could treat gentile nations in a cruel fashion, exposing those they had slain to be devoured by wild animals and by birds, cutting up with saws and axes those who were still alive, and making them pass through the brickkiln, 2 Samuel 12:31, also striking little children and hurling them to the ground. No one has ever been commanded to behave in these ways, nor has anyone ever been permitted to do so other than the kind of people in whom the nerve in the thigh has been put out of joint, 5051. Such spirits live beneath the right heel, where the adulterers who are also cruel dwell.

[2] In view of this it is astonishing that anyone should ever believe that that nation was chosen or elected in preference to any other one. Believing that they were so elected many people go on to convince themselves of the idea that one's life is of no consequence at all but that election and consequent acceptance into heaven is attributable to mercy alone, irrespective of the life one has led. Yet anyone of sound reason can see that to think in that way is to think contrary to the Divine. The Divine is mercy itself, and therefore if the attainment of heaven were attributable to mercy alone irrespective of the life one leads, all would be accepted, no matter how many these might be. To thrust anyone down into hell to suffer torment there, when it was possible for him to be received into heaven, would not be mercy but the opposite of mercy, and to elect one in preference to another would not be righteousness but the opposite of righteousness.

[3] Consequently those who have believed and convinced themselves of the idea that some have been elected and the rest have not been elected, also of the idea that admittance into heaven is attributable solely to mercy regardless of the life they have led, have been for the most part the kind of people who have led evil lives. These are told, as I have also heard and seen on several occasions, that the Lord never refuses anyone entrance into heaven, and that if they like they can find this out from experience. They are therefore raised up into some community of heaven whose inhabitants have led their lives under the influence of an affection for good, that is, they have led charitable lives. But when those raised up arrive there they begin, being evil, to suffer pain and inner torment because their life is contrary to that of heaven. And when heavenly light shines on them they look in that light like devils that are almost wholly devoid of human appearance. Some have sunken faces; some are all teeth, looking like crates; and some, who are different again, look like monsters. Thus they are horrified at themselves and hurl themselves headfirst into hell; and the deeper they can go, the better it is for them.