Systematic Theology, by Louis Berkhof - New Leaven

There are also several passages in which sheol and hades seem to designate the grave.
It is not always easy to determine, however, whether the words refer to the grave or to
the state of the dead. The following are some of the passages that come into
consideration here: Gen. 37:25; 42:38; 44:29; 29:31; I Kings 2:6,9; Job 14:13; 17:13; 21:13;
Ps. 6:5; 88:3; Eccl. 9:10. But though the name sheol is also used for the grave, it does not
necessarily follow that this is the original use of the word, from which its use to
designate hell is borrowed. In all probability the opposite is true. The grave is called
sheol, because it symbolizes the going down, which is connected with the idea of
destruction. For believers the Biblical symbolism is changed by Scripture itself. Paul
says that they go down in death as a grain is sown in the earth, from which springs a
new, a more abundant, a more glorious life. In the Old Testament the word sheol is used
more often for grave and less often for hell, while in the corresponding use of hades in
the New Testament the contrary holds.
D. THE ROMAN CATHOLIC DOCTRINES RESPECTING THE ABODE
OF THE SOUL AFTER DEATH.
1. PURGATORY. According to the Church of Rome the souls of those who are perfectly
pure at death are forthwith admitted to heaven or the beatific vision of God, Matt. 25:46;
Phil. 1:23; but those who are not perfectly cleansed, who are still burdened with the
guilt of venial sins and have not borne the temporal punishment due to their sins —
and this is the condition of most of the faithful at death — must undergo a process of
cleansing before they can enter into the supreme blessedness and joys of heaven.
Instead of entering heaven at once, they enter purgatory. Purgatory is not a place of
probation, but a place of purification and of preparation for the souls of believers who
are sure of an ultimate entrance into heaven, but are not yet fit to enter upon the bliss of
the beatific vision. During the stay of these souls in purgatory they suffer the pain of
loss, that is, the anguish resulting from the fact that they are excluded from the blessed
sight of God, and also endure “the punishment of sense,” that is, suffer positive pains,
which afflict the soul. The length of their stay in purgatory cannot be determined
beforehand. The duration as well as the intensity of their sufferings varies according to
the degree of purification still needed. They can be shortened and alleviated by the
prayers and the good works of the faithful on earth, and especially by the sacrifice of
the mass. It is possible that one must remain in purgatory until the time of the last
judgment. The Pope is supposed to have jurisdiction over purgatory. It is his peculiar
prerogative to grant indulgences, lightening the purgatorial sufferings or even
terminating them. The main support for this doctrine is found in II Maccabees 12:42-45,
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