Those of the elect - those whom God had chosen to salvation from before the foundation of the world - when they had died. they were held in Sheol - not Hell - until Christ's offering was completed. Upon completion, when the New Covenant came into effect, they then went to be in the new spiritual Jerusalem. They became saved the same way as everyone else: God chose them unto it.
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Mat 27:50-53 KJV]
50 Jesus, when he had cried again with a loud voice, yielded up the ghost.
51 And, behold, the veil of the temple was rent in twain from the top to the bottom; and the earth did quake, and the rocks rent;
52 And the graves were opened; and many bodies of the saints which slept arose,
53
And came out of the graves after his resurrection,
and went into the holy city, and appeared unto many.
Jas 2:11-12
11 For he that said, Do not commit adultery, said also, Do not kill. Now if thou commit no adultery, yet if thou kill, thou art become a transgressor of the law. 12 So speak ye, and so do, as they that shall be judged by the law of liberty.
The law of liberty is the 10 commandments and are not abolished.
The ordinances are abolished.
The law of liberty is not the ten commandments; the law of liberty is the law of Christ.
The ten commandments were abolished in/by Christ for those whom He saves. Christ is the Savior, and as Savior, His offering and sacrifice paid for all of our sins, past, present, and future without exception. That is how the NC could make the declaration of the verse below (Heb 8:12). And by that declaration, that any possibility of the NC being the ten commandments becomes completely eliminated and logically absurd: for if all of our sins and iniquities will He remember no more, then there is no purpose for the ten commandments to be in it as there is no judgement possible for those under it. Therefore, the law mentioned in the NC are the laws of Christ, not the laws of Moses. And that is the only way for the New Covenant to be correctly understood.
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Heb 8:12 KJV] 12
For I will be merciful to their unrighteousness, and their sins and their iniquities will I remember no more.
The law of liberty protects only those who have become saved by Jesus. Those judged guilty of the law of liberty, were not justified by the righteousness of Christ (becoming saved) - with His righteousness not being imputed to them as being their righteousness (which it is imputed to those He saves) - so their sin of working for their salvation (rather than of being saved by God's grace), means their sins remain in effect. They will therefore be judged by Him and found guilty in violation of that law as will all of the unsaved.
Romans 13:10, sums up the ten commandments, it teils us they are satisfied by the loving of our neighbors. What it doesn't say, however, is that by failing to satisfy it that we will be found guilty by God. We cannot be found guilty because we have been justified by Christ, not of ourselves - judged as though we have the perfection of the righteousness of Christ - Christ is the Savior, man is not.
This is given to us by the exceedingly great mercy and grace of God freely through Jesus Christ to those who in no way deserve it - of ourselves we are just as guilty as those whom He does not save.