The Bible indicates 3 compartments in Sheol; Paradise, or Abraham's bosom (Lk 16:22), where believers went after death, torments, where unbelievers went after death, and a compartment for angels that "left their first abode" (Jude 6).Sheol was the name of the"abode of the dead" which is often referred to as "the grave".
This is ancient Hebrew mythology...not Theology. IOW unrevealed theology.
Legacy was considered to be how a person lived forever amongst the living (at that time)[
Sheol was divided into two parts. One was full of their fathers and restful. The other area was not restful but tumultuous.
Jesus gave us a glimpse of Sheol in the story of a rich man and Lazarus.
Daniel is claimed to have been written about 605 BC. Moses wrote Genesis-Deut between 1450 and 1395 BC.The theology of a reward and afterlife wasn't known till Daniel wrote his book of prophecy.
And the writer of Hebrews wrote this about Moses:
Heb 11:26
He regarded disgrace for the sake of Christ as of greater value than the treasures of Egypt, because he was looking ahead to his reward.
NIV
Moses certainly knew about eternal rewards, and was looking ahead to his.
If your claim is correct, what did believers before Daniel think happened after they died?
If there is no afterlife, there is no need for a Messiah. I don't see how that squares with Scripture.
1 Sam 28:19 wasn't written in secret.And the secret things of God belong to the Lord...