As well as election, reprobation is the other doctrine that the churches never teach. Even when it is stated in the Scriptures and God talks about it in divers manners, it has become almost unknown to Christianity, but both these doctrines spring out of God’s Everlasting Covenant.
What is reprobation? This doctrine is a very important part of the Covenant. It is God’s way of telling the wicked that they have no part in His Kingdom. It is God telling those who do not believe His Word that they are destituted of His glory and they will never have a part of it.
Reprobation is the action of a Sovereign God (Rom. 9). He is who He is: The Great I Am. Satan deceived man in the Garden of Eden by telling him that he would be like God. Man believed the lie and lost his communion with His Creator. Man became enslaved to Satan and fell under his power.
Man died spiritually and could not have communion with God anymore. Then, he died physically. His body became subject to death and decay, and his soul was taken to Sheol after death.
Even when Sheol was the place for all who died before the cross, there was a group of people who were separated and had hope that they would be out of Sheol one day: the saints of the Old Covenant (before the cross). Christ accomplished this.
Christ fulfilled all the promises God had prepared for His people, and when Christ died on the cross, He went to Sheol/Hades and took His Old Covenant saints out to translate them to Paradise. Mat. 27:53
The rest, the reprobate, those who never knew or obeyed Jehovah God, were left in Sheol. They are joined daily by all the reprobates that have ever died after the cross, and they will remain there until the judgment of the last day. They were always strangers to the covenant of promise, having no hope and without God in the world. Eph. 2:12