The spirit does dismiss the law of the O.T and gives a new law. Had that O.T law been perfect, we wouldn't need Christ, it was precisely the fact that the law is not perfect is why Christ had to die. Therefore while it was the law of God, it was neither eternal nor perfect.
In the analogy of husband and wife which Paul give in the N.T, he say when a woman's husband is dead is only when she can marry a new husband.
Romans 7:1-3
Or do you not know, brethren (for I am speaking to those who know the law), that the law has jurisdiction over a person as long as he lives?
For the married woman is bound by law to her husband while he is living; but if her husband dies, she is released from the law concerning the husband.
So then if, while her husband is living, she is joined to another man, she shall be called an adulteress; but if her husband dies, she is free from the law, so that she is not an adulteress, though she is joined to another man.
and then
Romans 7:4
Therefore, my brethren, you also were made to die to the Law through the body of Christ, that you might be joined to another, to Him who was raised from the dead, that we might bear fruit for God.
See how Paul applies the analogy
WE AS BELIEVERS = THE WIFE
THE LAW = THE FORMER HUSBAND
THE NEW HUSBAND = JESUS CHRIST
We could not be joined to Christ if the former husband was alive but he, the Law, is not, because we have been made to die to the Law.
THE LAW IS DEAD TO US and WE ARE DEAD TO THE LAW.
King David would not have talked about its everlasting and eternal status.
Poetic exaggeration is pretty common in the O.T.
It would be a blessing if they missed the cairns and got lost on the way back. Or if
the Thing on the ice got them tonight.
I could only turn and stare in horror at the chief surgeon.
Death by starvation is a terrible thing, Goodsir, continued Stanley.
And with that we went below to the flame-flickering Darkness of the lower deck
and to a cold almost the equal of the Dante-esque Ninth Circle Arctic Night
without.
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