2 Chronicles deals with an oath given by King Asa and all the people of Jerusalem. It says right after that, that they repented, and: “2 Chronicles 15:15 (RSVCE): 15 And all Judah rejoiced over the oath; for they had sworn with all their heart, and had sought him with their whole desire, and he was found by them, and the Lord gave them rest round about.”

The Lord gave them rest.

Deuteronomy 17 is a much better example of what you are driving at. In this case mosaic law directly orders the stoning of those who engage in worship of other gods.

There are a few points that can be made in no particular order:

1. This law was binding upon the people of Israel, who had directly witnessed and seen their God.

2. The people of Israel were under an earlier covenant that the one extended to gentiles by Christ.

3. This was during the time of the prophets, before the final revelation of Christ, when God still spoke directly to man.

As for those who died before Christ, the Catechism of the Catholic Church explains that they remained in Limbo until the death of Christ, at which point Christ opened the gates of heaven to the just who died before him:

“Today a great silence reigns on earth, a great silence and a great stillness. A great silence because the King is asleep. The earth trembled and is still because God has fallen asleep in the flesh and he has raised up all who have slept ever since the world began. . . . He has gone to search for Adam, our first father, as for a lost sheep. Greatly desiring to visit those who live in darkness and in the shadow of death, he has gone to free from sorrow Adam in his bonds and Eve, captive with him—he who is both their God and the son of Eve. . . .”I am your God, who for your sake have become your son. . . I order you, O sleeper, to awake. I did not create you to be a prisoner in hell. Rise from the dead, for I am the life of the dead.” (CCC 635)

See also CCC637.